Research On The Microstructure And Properties Of Modil Red Nano-powders Reinforced Cast Al-Cu Alloy

Casting Al-Cu alloy is one of the most useful nonferrous materials in the industry, and it has fine strength and good high-temperature resistance property.So casting Al-Cu alloy is usually used to make elements under the situations of working in high temperature and endure middle level load environment.In order to further improve the microstructure and mechanical properties of Al-Cu alloy and enlarge its applied range.This paper is based on the studies of predecessors,and combined modified nano-powders technology and the traditional casting methods systematically. Modified nano-powders was put into the melt Al-Cu alloy by some helpful process under the lab conditions.The results showed that modified nano-powders could refine the grains of casting Al-Cu alloy and improve its mechanical properties and abrasion performance.In melt casting Al-Cu alloy,when change the content of modified powders,as to RE-Ti powders,when the addition amount is 0.1%,RE-Ti powder refine the micro structure best, tensile strength is 16.02% more than the original data,elongation ratio is 15.91% more than the original data,and the brinell hardness numerical value is 11.91% more than its original data.That is to say when the addition amount of RE-Ti powders is equal to 0.1%,the micro structure and properties of casting Al-Cu alloy are improved best.Under this circumstances, the abrasion performance of casting Al-Cu alloy reaches its highest level.For modified RE-SiC powders,when the content is 0.1%,the micro structure of casting Al-Cu alloy is refined obviously, tensile strength is increased by 15.47%,elongation ratio is increased by 12.88%, and the breinell hardness is increased by 7.53%, all of which has reached the maximum value at the mass of 0.1%.The wear weight is the lowest among the three addition amounts so the abrasion performance of casting Al-Cu alloy is improved best.To modified nano RE powders,when the content is 0.1%,the grain sizes of casting Al-Cu alloy are decreased remarkably,the tensile strength is 15.29% more than the initial value,the elongation ration is 5.30% more than the initial value,and the brinell hardness is 3.76% more than the initial value, which are the best properties of all the parameters.The weight loss percent is at the lowest value so that the casting Al-Cu alloy has got the best wear resistant property compared with the addition amount of 0.3% and 0.5% of RE-SiC powders.In melt casting Al-Cu alloy,when the addition amount of the three kinds of modified powders is fixed at 0.1%,compared the different microstructure,mechanical properties and abrasion performance of Al-Cu alloy when is added modified nano RE-Ti powders,modified nano RE-SiC powders and modified nano RE powders.The conclusion is that when RE-Ti powders is added,the grains of Al-Cu alloy is refined best,the mechanical properties reaches its maximum value and the wear resistance is improved best.The strengthening and toughing mechanism of modified nano powders in melt Al-Cu alloy shows that:the added modified powders not only has alloying contribution but also work as heterogeneous nucleus which can promote nucleation process and form dislocation loops to improve its properties.