车削加工对铍组织与性能的损伤

Effects of Lathe on Microstructure and Mechanical Properties of Beryllium

报道了不同车加工工艺对铍表层的损伤以及机加工损伤对铍力学性能的影响 ,建立了消除机加工损伤的方法。随车加工吃刀深度和走刀量的增加 ,铍材表面损伤层在 0 .1～ 0 .5mm范围内增加 ,机加损伤主要表现形式为形成表面孪晶 ,表层晶粒越粗大 ,孪晶密度越高。由于样品机加工时采用了较小的吃刀深度和走刀量 ,在金相显微镜下未发现表面裂纹。机加工损伤使铍的抗拉强度和延伸率均有较大降低。化学蚀刻是消除机加工损伤的较好方法 ,75 0℃退火能部分消除机加工损伤。消除机加工损伤后 。

The effect of a variety of lathe on the damage and mechanical properties of beryllium was studied, and the relieving machine damage of beryllium is solved. It is showed that the depth of the damaging layer of beryllium surface increases from 0.1 mm to 0.5 mm with the depth of cut and feed. Defect of the machine damaging layer consists of twin, and its density increases with the grain size of the surface layer. When the depth of cut and feed decrease greatly, few microcracks are found. The machine damage brings the tensile strength and the elongation value of beryllium to decrease. The chemical etching is an effective method of relieving machine damage, and the annealing at 750℃ is able to relieve the partial machine damage. The mechanical properties of beryllium are recovered after relieving machine damage.