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用RDL-50型拉伸蠕变试验机进行改装后的实验装置研究了铸态AgInCd合金在温度300~400℃及应力范围12~24 MPa内的压缩蠕变行为,分析了稳态速率与温度和应力的关系,计算了应力指数(n)和蠕变激活能(Q_a),并结合蠕变后样品在透射电子显微镜下的微观形貌及位错组态,探讨了合金的压缩蠕变机制。结果表明:随温度和应力水平的升高,合金的稳态蠕变速率增加。相比较指数关系,蠕变速率与应力之间更符合幂函数关系。300、350和400℃条件下,合金的蠕变应力指数n分别为3.31、4.09和5.77;12、18和24 MPa条件下,合金的蠕变激活能Q_a分别为68.1、103.7和131.6 kJ/mol。微观形貌以层错为主,孪生为300℃的主要蠕变机制,位错攀移生成位错墙为400℃的主要蠕变机制。
The modified experimental device with RDL-50 tensile creep tester is used to study the compressive creep behavior of as-cast AgInCd alloy at 300-400 ℃ and 12-24 MPa. The effects of steady state rate and temperature The stress exponent (n) and creep activation energy (Q_a) were calculated. Based on the microscopic morphology and dislocation configuration of the sample after creep, the compressive creep mechanism of the alloy was discussed . The results show that with the increase of temperature and stress level, the steady creep rate of the alloy increases. Compared with the exponential relationship, the creep rate and stress more in line with the power function relationship. Under the conditions of 300, 350 and 400 ℃, the creep stress exponent n of the alloy were 3.31, 4.09 and 5.77, respectively. Under the conditions of 12, 18 and 24 MPa, the creep activation energies of the alloys were 68.1,103.7 and 131.6 kJ / mol . The micro-morphology is dominated by layer faults, the twin is the major creep mechanism at 300 ° C, and the dislocation climbing creates a major creep mechanism at 400 ° C for dislocation walls.