精密零件的热处理变形控制技术

精密高频微波器件采用3A21 铝合金制造,焊接后会出现有规律的尺寸缩短现象,影响到微波器件的性能,生产合格率较低。为了提高产品的合格率,文中针对此问题,从零件结构、加工方法、内部组织变化等方面开展了相关研究。研究发现3A21 铝合金在高于再结晶温度的情况下长时间加热时容易在局部形成粗大的晶粒,晶粒结构的变化导致零件宏观尺寸的变化,从而出现精密高频微波元件焊接后尺寸缩短的现象。文中采取在零件加工前通过特定高温热处理工艺使高频微波组件尺寸稳定的方法来解决此问题。经过特定高温热处理后的工件在焊接后未出现尺寸缩短的情况,生产合格率为100% 。

Heat Treatment Technology for Deformation Control of Precise Parts

Precise high-frequency microwave devices are made of 3A21 aluminum alloy and have regular size shortening after welding. This will affect the performance of microwave devices and lead to low production qualification rate. In order to improve the production qualification rate, in this paper this problem is researched from the part structure, processing method and internal organization change. It is found that when the 3A21 aluminum alloy is heated for a long time above recrystallization temperature, coarse grains are easily formed locally. The change of grain structure leads to the macroscopic size change of parts and the size shortening of the microwave component after welding. In this paper the high-frequency microwave component size is stabled by specific high-temperature heat treatment method before processing. After specific high-temperature heat treatment , the component size is not shortened after welding and the production qualification rate of products reaches 100%.