注射成形高密度合金的变形控制

Distortion Contrl of Heavy Alloys for P/M

摘要:

研究了注射成形高密度合金的变形行为和变形控制。实验表明，在液相烧结过程中，由于重力作用导致粘性流动，合金试样发生变形。对W含量较高的合金，采用二步烧结工艺可以有效地控制变形。在此工艺中，压坯首先在粘结相熔点以下温度烧结，形成W连通骨架，然后在高于粘结相熔点以上的温度下烧结较短时间以达到全致密；对于W含量较低的高密度合金，将原始混合粉末采用机械合金化，然后再进行固相烧结，可以得到性能很高的无变形的合金。

Abstract:

The distortion behavior and distortion controlling processes of PIM tungsten based heavy alloys were studied in this paper. Liquid phase sintering distorts the samples due to the large difference in density between W phase and liquid phase. The two step sintering process can effectively decrease the distortion of the alloys with higher tungsten contents. For the alloy with low tungsten contents, the powder mixture can decrease the sintering temperature of the alloy for full densification with good mechanical properties.