热处理对热等静压制备的TaW10合金氧含量及力学性能的影响

Influence of Heat Treatment on Oxygen Content and Mechanical Properties of TaW10 Alloy Fabricated by Hot Isostatic Pressing

以氢化-脱氢后的TaW10合金粉末为原料,采用热等静压技术制备了TaW10合金,并对其进行1 800~2 200℃热处理,研究了热处理温度与TaW10合金氧含量及力学性能之间的关系。结果表明,随热处理温度升高,TaW10合金拉伸断裂模式从脆性解理断裂先转变为脆性沿晶断裂,再转变为塑性韧窝断裂。合金强度随热处理温度升高先增大后减小,经2 100℃热处理后达到最大值。当热处理温度升至2 150℃时,热等静压制备的TaW10合金开始表现出塑性变形特征。经2 000℃热处理后,合金氧含量明显降低,此后随热处理温度升高,氧含量变化不明显。热等静压制备的TaW10合金仅在氧含量足够低且经2 150℃以上温度热处理后才具有较好的强度与塑性。

TaW10 alloy was fabricated by hot isostatic pressing with hydrogenation-dehydrogenation powder as the raw material. And then TaW10 alloy was subjected to heat treatment at 1 800-2 200 ℃.The relationships between heat treatment temperature and oxygen content or mechanical properties of TaW10 alloy were studied. The results show that with heat treatment temperature improved, the fracture mode of TaW10 alloy changes from brittle cleavage fracture to brittle intergranular fracture and then to ductile dimple fracture. The strength increases firstly and then decreases with heat treatment temperature improved, and reaches the highest value at 2 100℃.When the heat treatment temperature is up to 2 150 C,TaW10 alloy starts to show ductile deformation characteristics. TaW10 alloy has sharply declined oxygen content after heat treatment at 2 000 ℃,and then there is no obvious change of oxygen content with further im- proved heat treatment tempreature. TAW10 alloy has good strength and ductility only when its oxygen content is sufficiently low and its heat treatment temperature is above 2 150 ℃