论文部分内容阅读
研究了液相烧结钨基高比重合金(95W-3.5Nj-1.5Fe)烧结后热处理对力学性能的影响.经过1200℃真空热处理,合金中氢含量降低了70%,强度提高约30%,延性显著增加,同时断裂韧性值也有提高。通过扫描电镜断口金相观察,发现氢含量高的试样显示了基体-钨颗粒相界面断裂,对氢含量低的试样,断口微观形态由沿相界面断裂方式过渡到相界面断裂和部分钨颗粒解理断裂方式,说明削弱了氢脆,加强了相界面结合力,从而改善了合金的力学性能。对氢含量高的试样,作了离子探针分析,其结果指出钨颗粒周围含氢最较高,相界面有氢的富集,它是导致相界面断裂的根源。
The effect of heat treatment on the mechanical properties of liquid phase sintered tungsten-based high specific gravity alloy (95W-3.5Nj-1.5Fe) after sintering was studied.The hydrogen content in the alloy decreased by 70%, the strength increased about 30% after 1200 ℃ vacuum heat treatment, Significantly increased, while the fracture toughness values also increased. The results of scanning electron microscopy showed that the samples with high hydrogen content show the rupture of the interface between the matrix and the tungsten particles. For the samples with low hydrogen content, the fracture microstructure changes from the rupture along the phase interface to the rupture of the phase interface and part of the tungsten Particle cleavage fracture mode, indicating weakened hydrogen embrittlement, strengthening the phase interface binding force, thereby improving the mechanical properties of the alloy. Ion-probe analysis was performed on samples with high hydrogen content. The results show that the hydrogen content around the tungsten particles is the highest, and the enrichment of hydrogen at the phase interface is the root cause of phase interface fracture.