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APRIL 10-Officially, spring comes to the Great Lakes on March 21 as it does elsewhere in the country but in the Superior district continued snow and freezing until late in March have caused citizens in Duluth to place their bets on April 15 for the first ore vessels if the ice breakup is left to Mother Nature. North and west of Duluth and near the eastern end of the Mesabilies the little town of Aurora, population 1100. As the little v-nosed snowplow, pride of the community, shuttled back and forth clearing Aurora's few sidewalks, the crowd in Bradich's Cafe were more interested in the impending high school state championship basketball tournament in Minneapolis than in the outcome of Erie Mining Company's petition for water rights for their proposed 10 million ton taconite concentrating plant. Such a plant would employ 4500 workmen, and at the prevailing ratio of 10 people for every mine worker in Minnesota, this would mean a 45,000 increase in population for Aurora and the vicinity in the next few years. Downstate fishermen are alarmed at the flurry of activity by the mining companies in pushing plans for large scale recovery of iron from taconite. Inconvenience to these gentlemen will be inconsequential when compared with the vast increase in payrolls for range communities. Oliver is pushing the construction of a fine ore agglomeration plant at Virginia which will give them valuable experience for projected taconite processing. Oglebay, Norton & Co. is ready to go at Beaver Bay, north of Duluth, as the right of way for a railroad from Babitt to Beaver Bay is secured as well as permission to dispose of tailing into Lake Superior at the site of the proposed concentrating plant. This company is also doing research in agglomeration at Ashland, Ky., in cooperation with other interests. The financing is yet to be worked out. Of the four possibilities for agglomerating taconite concentrate-sintering, pellitizing, nodulizing and briquetting-the prospects for pelletizing appear the most favorable., It seems likely that 60 cents per ton can be saved by this process over sintering because only 1 to 2 pct of coal is required as compared with 7 pct for sintering. One reason for the lower coal consumption is that the chemical transition of magnetite to hematite which transpires in the pelletizing process is exothermic.

Jan 5, 1950

APPLICATIONS for loan contracts for the exploration, development and mining of strategic and critical metals and minerals are now being accepted by the Department of the Interior. The RFC is authorized and directed by Executive Order 10161 to make such loans but the Secretary of the Interior must pass on the necessity for the loan. Applications should be addressed to James Boyd, acting deputy administrator, Defense Minerals Administration, Department of the Interior, Washington, D.C. rather than to the Field Offices of the Bureau of Mines as was first planned. Application forms are not yet available but it has been learned that data accompanying the application should include the known quantity and grade of reserves, the anticipated rate of production, the equipment, supplies, and man power required for the additional production, etc.

Jan 12, 1950

THE research and policy committee of the Committee for Economic Development, a non-profit research organization composed of leaders in industry and the professions, including such prominent figures as Dwight D. Eisenhower, Paul G. Hoffman, and Charles E. Wilson, recently published a report entitled "How to Raise Real Wages." Since its founding in 1942 the CED has initiated many objective studies on matters of national economic policy, and has gained a fair measure of prestige from its activities. The CED's latest report cites the more than three- fold rise in real wages in the United States in the past 50 years and attributes the accompanying improvement in the standard of living to the great in- crease in production per man hour. The report states that in order for production to continue rising in the future with the attendant increase in real wages four basic conditions must be manifest: (1) better methods, (2) more capital, (3) better training of workers, and (4) better management. The report cautions that although prospects for increases in output per man hour are good "it is desirable that steps be taken to encourage such a rise."

Jan 8, 1950

MAY 17-The last bit of verbal sod had hardly come to rest on the grave of the coal industry-which grave was being eagerly dug with typewriters and microphones by administration hangers-on and even an operator or two-when its leaders gathered for the 1950 Coal Convention of the AMC in Cincinnati on April 24. Surprisingly, mourning clothes were not being worn but the boys had on their diggers preparatory to digging their way out from under the muck. High costs created by wage and welfare demands, together with work stoppages, have caused markets to shrink, but even so, an optimistic air still prevailed as new techniques were disclosed at technical sessions. The administration, however, came in for its share of knocks.

Jan 6, 1950

JAN. 17-In what appears to be a general spirit of post-Christmas emotional malaise, most adult Americans have bidden farewell to the Forties and turned with no perceptible enthusiasm toward the Fifties. The dying decade had started amid a phoney war which verged on the romantic, stirred the pulse with excitement and seemed far away. A phoney peace dominates the new decade. The romance is no longer there. Nor is the excitement. Nor is the distance. While most of the world preferred to be chronologically correct and hold off for another year before celebrating the demise of the first half of the twentieth century, the United States with true competitive enterprise and a great whirl of words scurried into the second half a year early. This undue haste might perhaps have been dictated unconsciously by a yearning for the pattern of history to be repeated. For many centuries, ever since Roman times, the second half of most centuries tended to be far more tranquil than the first half. In Washington, Mr. Truman got on both sides of the mid-century line with all the aplomb of a good politician. He told Congress early in January that "the state of the Union continues to be good," as it nears "the midpoint of the twentieth century." Later he spoke of moving forward into the second half of the century. He promised an infinitely better life for everyone, whichever side of the mid-century line, and reaffirmed his prescription toward that end: assistance for small businesses; more houses for the middle-income groups; tougher anti-monopoly laws, retention of rent controls; development of natural resources; better insurance against the hazards of old age, idleness and unemployment; better medical care and education, civil rights legislation; new labor relations law and production payments to support farm incomes. All this was to be coupled with suggestions on how to balance the budget. The bloody and confusing 1940's had brought to most men's minds a fear of the future such as they had not known for centuries, and Mr. Truman's objective is to temper that fear. Only time will tell whether the terminal point of such a philosophy would or would not belie the old English proverb citing inability to both eat and have a cake. Brave words to the contrary, the national budget persisted in sliding off into the red. The smell of further inflation was equally persistent. And just to impart a little more zip to the trend, the American Federation of Labor announced its intention of seeking "substantial" and "large" wage increases this year. The AFL forewarns of a business slump after June and a 10¢ an hr wage in¬crease for each worker "will be enough to reverse the prospective downward trend and start a rise." Thus it goes-"the way to halt a drop in demand for labor is to raise the price of labor." Elsewhere in the harassed world, beleagured individualists in New York achieved a local triumph of sorts for one of the freedoms denied by the Soviet and Nazi systems-the right of escape, some escape at least, from the servitude to decibels. Grand Central Station weakened perceptibly at Christmas on its 5-min commercials and bore down heavily on "Hark, The Herald Angels Sing," and on New Year's Day capitulated entirely by abandoning the broadcasting of canned music and slugs of advertising slogans. In Europe, M. Bidault's Assembly majority fell away and newspaper accounts of the incredible monstrosities of political trials beyond the iron curtain were supplanted by headlines marking the birth of Princess Yasmin. The latter was surrounded by Byzantine splendor but otherwise showed no apparent deviation from the accepted norm. In Western Germany, Dr. Adenauer began to speak up more boldly, and the whole fabric of Allied policy towards the defeated enemy further dossolved under the impact of rivalry with the Russians. In the Far East both the Americans and British seem somewhat embarrassed by Chiang Kai-shek's refusal to lie down. Dual thinking regarding the "squalid and useless struggle in the China seas" is such that newspapers give sympathetic accounts to an American ship running supplies to the Communists at Shanghai while calling for help for the recognized Chinese government in Formosa. And with Britain recognizing Communist China they may well have to team up with Russia against the United States to kick the Chinese representative off the UNO Security Council, the Far Eastern Commission and the Allied Council in Tokyo. Far Eastern policy has never been a bipartisan matter and as General Chiang retreated to his final redoubts in Formosa and Hainan, a number of Republicans pecked away at Administration lassitude. Senator Smith advocated the occupation of Formosa and Messrs. Hoover and Taft asked for use of the Navy. Mr. Acheson has stood firm, however, against military aid. None the less, a study will be made of the Generalissimo's chances. Mr. Truman has a private purse of $75 million for the Far East and some $94 million in frozen ECA funds. Mr. Truman will likely trade some of this money for support of new Marshall plan appropriations, always mindful, of course, of Mr. Acheson's plan to drive a wedge between the Chinese and Moscow, and his wish to avoid any revival of imperialist nightmares throughout the Orient. Mr. Acheson is very convinced that the victories of Communism in China will be short-lived and South Asia will not fall

Jan 2, 1950

By Scott Lawson

BOB FALCONER: Our next topic leader is Scott Lawson. Scott is manager of human resources for Independence Mining Company, Cripple Creek and Victor Gold Mining Company, Victor, Colorado. Scott has 25 years of human resources management experience in the mining industry, surface and underground, precious and base metals. His topic this morning is "It's the Employee That Counts." SCOTT LAWSON: When reviewing the topic of productivity in a union versus nonunion workplace, we need to look at who, and not what, can make the difference in ensuring the success of a production-oriented operation. It's not explicitly whether the property is unionized or not, but whether the employee team (including the "management group") is working together to accomplish common, shared, and meaningful goals. The bottom line is what action or actions can be taken to develop trust and to strengthen working relationships that challenge and compel employees to willingly share their particular areas of expertise. I want to share a real-life experience that happened to me during the summer of 1961. Perhaps some of you will be able to relate to the following story. I was an 18-year-old fresh out of high school, ready for my first true work adventure. I found summer employment for myself and two friends with the New York Central Railroad in Cleveland, Ohio. Our jobs were as laborers, laying ties and rails, and unloading ballast. We made $2.62 an hour. We were fat cats! My friends and I took on the job with a great deal of vigor, to the dismay of our fellow workers. These workers were unionized by the Railway Workers, which I believe were affiliated with the Teamsters. Talk about being naive, we wrote the book in 1961. When we took the jobs, we did not realize the employees were represented by a union, even though we didn't think they worked too hard. Within our first two weeks of work, we established new daily records for laying virtually twice as many ties as had been standard, and we nearly tripled production by the end of our hall of fame railroad careers. We even took naively to the next level by lining up the ties for our afternoon work shift during our lunch break. In 1961, we thought we were the Mantle, Maris, and Colavito of tie laying. For the younger set in the audience, we would have felt like the McGwire, Griffey Jr., and "The Big Hurt" Thomas of tie laying. A section of the union contract allowed for a 60-day probationary period during which the employee was evaluated and also exempt from joining the union. I will venture to say that, to none of your surprise, on day 60 we were asked to join the union, and on

Jan 1, 1998

National Minerals Advisory Council A meeting of the National Minerals Advisory Council on August 3rd in Washington, D. C., indicated the vitally important part that the mining industry is to play in the mobilization program. Director James Boyd of the Bureau of Mines told the Council that the Department of the Interior would review the recommendations of all the Council's commodity committees with regard for mobilization planning in the light of the changed international picture. The Council was requested to reactivate its commodity committees and have them gather all available data on supplies, their sources and availability and present and potential production of the minerals and metals represented on each committee. Data on labor, machinery, transportation, automotive and stationary equipment, power, fuel, lumber, water supply are a few of the important items called for in the reports, which are to be presented at a meeting of the Council on September 1 at Salt Lake City. The material in the reports will become the basis for discussing metal and mineral requirements at that time. Discussion at the meeting bared several $64 questions, probably the most important of which are the following: 1. Which of the war-essential metals and minerals and in what quantities can we reasonably expect to get them from abroad under threat of submarines? 2. How are we going to meet the manpower problem posed by (a) migration of labor from mining to manufacturing since the end of World War II and (b) the draft and the calling up of reservists? Opinion was expressed by industry spokesman at the meeting that the function of complying with mobilization requirements be left to those in the industry itself; that is, those having the "know how." This view contended that any administrating governmental agency should be kept as small and streamlined as possible. There was general sentiment against the reactivation of the wartime Premium Price Plan or other bonus plans as a stimulus to production. The thought was emphasized that what was needed was a change in the basic conditions which have fostered the decline in domestic mining activity in the postwar years. One such condition, long overdue for correction, is the tax structure as it applies to mining enterprises. Many quarters both in industry and in government favor tax relief along the lines suggested in the six tax recommendations by the Council to the Secretary of the Interior last December. The Council adopted a resolution expressing a feeling that the following tax recommendations are still feasible and desirable and will accomplish as much toward increasing exploration for new deposits (thereby subsequently increasing production) as will government loans for exploration: (1) Losses from unprofitable ventures should be allowed corporations, partnerships, or individuals as ordinary deduction against current income. (2) Development costs after discovery should be recognized as operating expenses. (3) Allowance for depletion should be made to the stockholder as well as to the corporation. (4) Income should not be taxed without full allowance for losses of loss years. (5) Adequate allowances for percentage depletion should be made. A discussion of the manpower problem led to the Council's acceptance of a resolution advising that "military authorities should proceed with caution in depriving the mining and metallurgical industry of its manpower." The resolution strongly urged that no personnel "directly engaged in exploration, development, production or supervision (of strategic and critical materials) should be drafted for the armed forces, at least until the anticipated demands upon these producers are clarified." Stockpiles The Munitions Board's "Stockpile Report to the Congress" of July 23, 1950 revealed: (1) The total estimated value of the stockpile objective is $4,051,714,510 at the close of fiscal year 1950. (2) The total value of the stockpile on hand, at the close of fiscal 1950 was $1,556,154,352 or 38.4 pct of the total stockpile objective. An additional $494,948,060 was on order, making a total of 50.6 pct on hand plus the amount on order. (3) Materials obtained for the stockpile by the ECA from January to June 1950 amounted to $13,112,085, while development projects by ECA during this period involved the expenditure of $9,322,000, mainly with counterpart funds. Shortly after the start of the Korean conflict it was felt that Congress ould appropriate greatly increased sums for the purchase of materials for the stockpile. This stimulus to the program may increase the dollar earnings of those European nations that are present or potential contractors in our stockpiling program. Such a development would mean that these nations could add to their gold reserves, thereby stabilizing their respective economies and hastening recovery. This seems to be the picture for the next six months anyway. The "bug" appears when it is realized that the increased threat of total world war actually may retard recovery in Europe as nations on the continent may feel inclined to devote more of their resources to defense programs. Industries Essential to Defense The Department of Commerce in response to a request by the Department of Defense issued on August 3, 1950 a "Tentative List of Essential Activities" as a "guide for calling up for active duty members of the civilian components of the Armed Forces." The list includes the following: Primary Metal Industries. Included herein are establishments engaged in the smelting and refining of ferrous and nonferrous metals from ore, pig, or scrap. Metal Mining. This category includes establishments primarily engaged in mining, developing mines or exploring for metallic minerals (ores). This group includes all ore dressing and beneficiating operations. Anthracite Mining, Bituminous Coal and Lignite Mining, Crude Petroleum and Natural Gas Extraction, Mining and Quarrying of Nonmetallic Minerals, Except Fuels. Challenge to the Mining Industry The source of our country's great strength lies in its capacity to produce. In times of stress such things as national morale and manpower are all-important but without a capable industrial machine we would be helpless. That machine must be fed with minerals and metals in order to generate and maintain momentum sufficient to insure success. Consequences of the lack of adequate supplies of essential metals and minerals to increase and sustain our industrial power are not pleasant to contemplate. It is absolutely imperative that we put forth Herculean effort to guarantee ample supplies of such essential materials as copper, lead, zinc, manganese, antimony, mercury, tungsten, tin, chromite, nickel, cobalt, iron ore and rubber. The mining industry faces a challenge more serious than ever existed before in the history of our country. The industry must be equal to the task.

Jan 9, 1950

CHAIRMAN DOUGHTON of the House Ways and Means Committee announced on September 23 that the committee has scheduled public hearings on an excess-profits tax, beginning on November 15, 1950. In the meantime, the staff of the Joint Committee on Internal Revenue Taxation and the staff of the Treasury Department are to confer jointly on this question in the hope that such conferences may result in the preparation of a report on excess-profits tax proposals which could be used as a basis for testimony before the committee. It is thought that this procedure may aid in the draft of an excess-profits tax bill for introduction in the House when Congress reconvenes on November 27.

Jan 11, 1950

FEB. 17-The past month found the average citizen backed off just a little more into his blind corner staring glassily at hydrogen bombs, unbalanced budgets, John L. Lewis, more inflation, a rising wave of strikes, the country's only active battleship on a mudbank, a famous scientist in gaol as a traitor, a favorite actress on a Roman holiday, and rising mountains of potatoes, butter and eggs begging for destruction. About the only bright spot has been industrial activity and employment, but even these are menaced by the coal shortage. Most industries have orders on hand or in prospect to warrant high operations for some time to come. The trend of the Reserve Board's production index is upward except as strikes may interfere. There has been heavy buying at the seasonal merchandise shows, particularly in furniture and house-hold goods. The demand for goods of this kind illustrates greater confidence in the Spring outlook than was generally felt a year ago. Further, the demand also reflects improved market positions due to curtailment of output and reduction of inventories in 1949 and sustained consumer buying power. It demonstrates the strong support that is given directly to many businesses, and indirectly to all, by the phenomenal construction activity that is now under way. The Commerce Department places the number of new dwelling units started in 1949 at the new all-time high of 1,019,000.

Jan 3, 1950

D EC. 20-The spirit of Christmas and good will toward men has managed a few brief appearances on the front pages, welcome relief from man's usual ill-will toward man. A couple politicos did their best to brighten the scene by well-publicized romances. There was a general exodus to Florida to patch up nervous systems, and even the UNO quieted down as Mr. Vyshinsky departed for home via Eastern Germany. Before going he opened up a preliminary bombardment for the worldwide "communist peace offensive," and it is now the duty of the 600 million (according to the Cominform) ideological converts to press home the attack. In Washington, Mr. Lilienthal resigned as Chairman of the Atomic Energy Commission and demonstrated again the difficulty of government to retain the services of capable men. The President has yet to appoint another victim- possibly someone nicely noncontroversial and timid. So might the critics be appeased, but it would bode ill for the rapid exploitation of peaceful uses of atomic energy, the relaxation of excessive secrecy, wider sharing of developmental work with friendly nations and possible revision of the Acheson-Lilienthal proposals for inter- national control of the atomic bomb.

Jan 1, 1950

Abandoned Mme - A mine that a not producing any mineral and will not continue or resume operation Abatement - The lessening of pollution effects Acidity - A measure of the extent to which a solution is acid Acid Mme Drainage - Any acidic water draining or flowing on, or having drained or flowed off, any area of land affected by mining

Jan 1, 1975

By William E. Ford, Edward Salisbury Dana

430. The more important of the special properties of a mineral species with respect to heat include the following: Fusibility; conductivity and expansion, especially in their relation to crystalline structure; change in optical characters with change of temperature; specific heat; also diathermancy, or the power of transmitting heat radiation. The full discussion of these and other related subjects lies outside of the range of the present text-book. A few brief remarks are made upon them, and beyond these reference must be made to text-books on Physics ant1 to special memoirs, some of which are mentioned in the literature (p. 305).

Jan 1, 1922

By William E. Ford, Edward Salisbury Dana

1. Normal Class (25) Barite Type 2. Hemimorphic Class (26) Calamine Type 3. Sphenoidal Class (27) Epsomite Type Mathematical Relations of the Orthorhombic System Crystallographic Axes. - The orthmhombic system includes all the forms which are referred to three axes at right angles to each other, all of different lengths. 296 Any one of the three axes may be taken as the vertical axis, c. Of the two horizontal axes the longer is always taken as the b or macro-axis * and when orientated is parallel to the observer. The a or brachy-axis is the shorter of the two horizontal axes and is perpendicular to the observer. The length of the b axis is taken as unity and the lengths of the other axes are expressed in terms of it. The axial ratio for barite, for instance, is a : b : c = 0'815 : 10 : 131. Fig. 296 shows the crystallographic axes for barite.

Jan 1, 1922

By V. L. Nkuna, S. R. Amos, T. Naidoo

"Ivanhoe Mines’ Kamoa copper project is a recently discovered high-grade copper sulphide deposit in the Katanga Province of the Democratic Republic of Congo. The mineralization identified to date within the resource is typical of sedimentary-hosted stratiform copper deposits and comprises three distinct units: supergene, mixed, and hypogene mineralization. Since 2010, various metallurgical test work campaigns have been conducted on drill core from different areas within the deposit in line with resource expansion. The most recent bench-scale flotation test work has shown positive repeatable results. The work was conducted on a composite sample of drill core from the southern part of the Kamoa resource. The sample is representative of the first four to five years of planned production, when Ivanhoe Mines intends to produce clean, highgrade copper flotation concentrate. A detailed test work roadmap developed from first principles for the campaign led to an optimum flow sheet for treating the Kamoa mineralization. Copper recoveries of 88.3%, at a concentrate grade of 39.0% copper, were achieved using a composite sample — an improvement on the previously published 85.9% life-of-mine average copper recovery indicated in the November 2013 Kamoa Preliminary Economic Assessment. IntroductionThe Kamoa project is a newly discovered, very large, stratiform copper deposit with adjacent prospective exploration areas within the Central African Copperbelt, approximately 25 km west of the town of Kolwezi in the Democratic Republic of the Congo (DRC) and about 270 kilometres west of the provincial capital of Lubumbashi. Ivanhoe Mines holds its 95% interest in the Kamoa copper project through a subsidiary company, Kamoa Copper SA Limited SPRL, and DRC government owns 5%. The project location is indicated in Figure 1.In January 2013, a new independent mineral resource estimate ranked Kamoa as Africa's largest high-grade copper discovery and the world's largest undeveloped highgrade copper discovery. At this time, Ivanhoe Mines had estimated discovered Indicated Mineral Resources of 739 Mt grading 2.67% copper, containing 43.5 billion pounds of copper, and Inferred Mineral Resources of 227 Mt grading 1.96% copper, containing 9.8 billion pounds of copper, as demonstrated in the Preliminary Economic Assessment (PEA) (AMC, 2013). A 1% copper cut-off grade and a minimum vertical mining thickness of 3 m were applied in each classification."

Jan 1, 2016

By Jess Harding

Oyu Tolgoi investment agreement now in full, legal effect Successful completion of a series of conditions to 2009 Investment Agreement was announced March 31, 2010. Full-scale construction now set to begin. First copper-gold commercial production from Oyu Tolgoi expected in 2013. 34% of holding company Oyu Tolgoi LL Cacquired by Erdenes MGL, a Mongolian state-owned resources company. Remaining 66% will continue to be owned by Ivanhoe Mines. ?After 9 years of discoveries at Oyu Tolgoi, a big piece of the future of copper and gold in Asia is poised to become a reality.?

May 1, 2010

By Jacob Chacko

The Izmit Bay bridge, a 3-km-long suspension bridge crossing of Izmit Bay, Turkey is planned to be constructed in one of the most seismically active places in the world. The site, which has the potential to experience significant earthquakes associated with the relative motion accommodated on the North Anatolian Fault, is underlain by deep deposits of soft soils, and areas of unstable and liquefiable soils. Characterizing the seismotectonic setting, foundation soil conditions, potential fault locations, as well as other geohazards was a critical component for the project concessionaire to finance the project and obtain meaningful bids for bridge design and construction. Given the Build Operate Transfer (BOT) funding mechanism, executing this work in the least possible time was critical to the concessionaire?s financing scheme. Fugro was retained to provide geotechnical, geological, and seismological evaluations for the project region, and to generate data for contractors to develop reliable designs and bids. The uncertainties in these data made it difficult for the BOT concessionaire to finance the project and tender Bridge design and construction. The investment in an early and comprehensive site characterization program to evaluate and quantify those uncertainties allowed the concessionaire to save schedule, provide a robust bid basis to bridge contractors, and persuade banks to finance what was perceived to be a relatively high risk project.

Jan 1, 2011

By Sergio N. Monteiro

Polymer matrix composites have been applied in components such as helmets and shielding for which toughness is a major requirement. Natural fiber presents interfacial characteristics with polymeric matrices that favor a high impact energy absorption by the composite structure. The objective of this work was then to assess the Izod impact resistance of polymeric composites reinforced with different amounts, up to 30% in volume, of a promising high strength natural fiber from the Amazon region known as curaua. The results showed a remarkable increase in the notch toughness with the amount of incorporated curaua fibers. This can be attributed to a preferential debonding of the fiber/matrix interface, which contributes to an elevated absorbed energy.

Jan 1, 2009

By Carlos Maurício F. Vieira, Lázaro A. Pizatto, Marcus Paulo Cardoso, Sergio Neves Monteiro, Joao Victor C. Nunes, Gustavo S. R. Matheus, Frederico M. Margem

The interest in composites with natural fibers is due, among other factors, to the growing worldwide concern with the preservation of environment and renewable raw materials. The natural fibers have many particular properties that make them an attractive alternative to traditional synthetic fibers. The advantages of using these fibers are: low cost, renewability, biodegradability, low toxicity, abundance and specific strength. The searching for new suitable, economically viable and technologically advanced materials justifies the accomplishment of this work that aims at comparing the mechanical behavior of polyester matrix composites with epoxy matrix composites reinforced with hemp fibers Izod impact tested. The specimens with dimensions: 10 63 12.7 mm, made in different volume fractions of fiber: 0–30 vol%. The samples were tested at PANTEC pendulum model XC-50 located at LAMAV/UENF. With this research was possible to analyse the mechanical properties of these two new materials.

Mar 1, 2018

By Fernanda de Paula, Lázaro A. Rohen, Sérgio N. Monteiro, Rafael G. de Castro, Carlos Maurício. F. V, Maycon A. Gomes, Frederico M. Margem, Anna C. C. Neves

Synthetic fiber has been gradually replaced by natural fiber, such as lignocellulosic fiber. In comparison with synthetic fiber, natural fiber has shown economic and environmental advantages. The natural fiber presents interfacial characteristics with polymeric matrices that favor a high impact energy absorption by the composite structure. However, until now little has been evaluated about the hemp fiber incorporated in polymeric matrices. This study has the purpose of evaluate the impact resistance of this kind of epoxy matrix composite reinforced with different percentages of hemp fibers. The impact resistance has substantially increased the relative amount of hemp fiber incorporated as reinforcement in the composite. This performance was associated with the difficulty of rupture imposed by the fibers resulting from the interaction of hemp fiber / epoxy matrix that helps absorb the impact energy.

Jan 1, 2015

By Ygor Macabu de Moraes, Jean Igor Margem, Carolina Gomes Dias Ribeiro, Frederico Muylaert Margem, Sergio Neves Monteiro, João Batista Vasconcelos

A natural fiber presents interfacial characteristics with polymeric matrices that favor a high impact energy absorption by the composite structure. The objective of this work was then to assess the Izod impact resistance of polymeric composites reinforced with one or two layers of batt malva and jute fibers. The results showed are markable increase in the notch toughness with increasing layers of mauve blankets and jute.This can be attributed to a preferential debonding of the fiber/matrix interface, which contributes to an elevated absorbed energy.

Mar 1, 2017