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研究了热处理对W-80Cu板材组织演变和性能的影响.采用扫描电镜(SEM)和透射电镜(TEM)观察了W-80Cu板材的微观结构和断口形貌,并对其电导率和力学性能进行了研究.结果表明,热处理后试样的电导率和延伸率均高于未热处理试样,而硬度和抗拉强度均低于未热处理的试样.在600℃下热处理1.0h,W-80Cu板材的电导率和延伸率最大,韧窝深而密,且分布均匀.W-80Cu板材的室温拉伸断裂方式主要是沿晶断裂和韧窝断裂的混合断裂.当热处理温度在800 ℃左右及以上,断裂韧窝变得深浅不一,大小也不均匀,局部出现断裂台阶和准解理断裂.当时间超过1.0h时,出现局部韧窝变大,铜的撕裂脊变长,这与铜晶粒的再结晶长大有关.在热处理过程中W-80Cu板材中的钨相没有明显变化,但试样中钨颗粒周围大量位错及材料中的晶界明显减少.纳米钨颗粒与铜基体之间存在良好的界面关系,这有利于材料强度的提高.“,”The effect of heat-treatment on the micro-structure evolution and properties of W-80Cu sheets was investigated.The micro-structure and fracture appearance of W-80Cu sheet were observed by scanning electron microscope(SEM)and transmission electron microscopy(TEM).The electrical conductivity and mechanical properties were also investigated.The results indicate that the electrical conductivity and elongation of the specimens after heat-treatment were higher than those of the un-heated while their hardness and room temperature tensile strength was lower.The maximum electrical conductivity and elongation of W-80Cu sheet after ageing at 600 ℃ for 1.0 h were achieved and the dimples were deeper and more compact,and its size and distribution became uniform.The tensile fracture of W-80Cu sheet was the main manner of the inter-granular brittle fracture with dimple fracture.When raising the heat-treatment temperature around or above 800 ℃,the size and depth of the dimples became different and the steps and quasi-cleavage appeared at the local zone.Once the time was above 1.0 h,the local dimples became big and the tearing ridges of copper got longer due to the recrystallization growth of copper grains.During the heat-treatment,tungsten phase in W-80Cu sheet had not an obvious change,but a lot of dislocations around tungsten particles and grain boundary decreased in amount.Both tungsten nano-particles and copper matrix had a good interface relation,which benefited to the strength enhancement.