【摘要】 研究了添加Cr对形变退火态Ti-50.8Ni形状记忆合金氧化行为及组织和相变特性的影响。结果表明,添加微量Cr后,Ti-Ni合金的再结晶温度和抗氧化能力有所降低,相变热滞增加,相变温度大幅度降低。随退火温度升高,Ti-50.8Ni合金冷却/加热时的相变类型发生由A→R→M/M→R→A型向A→R→M/M→A型再向A→M/M→A型转变(A-母相,R-R相,M-马氏体),Ti-50.8Ni-0.3Cr的相变类型发生由A→R/R→A型向A→R→M/M→R→A型再向A→R→M/M→A型再向A→M/M→A型转变。随退火温度升高,二合金的R相变温度和M相变热滞降低,M相变温度升高,R相变热滞变化不大,保持在4℃左右。更多还原

【Abstract】 The effects of adding Cr on oxidation behavior,microstructure and transformation characteristics in Ti-50.8Ni shape memory alloy were investigated.The results show that after adding trace Cr,the recrystallization temperature and antioxidation ability decrease,temperature hysteresis increases,and transformation temperature decreases remarkably for Ti-Ni alloys.With increasing annealing temperature,the transformation types of Ti-50.8Ni alloy change from A→R→M/M→R→A to A→R→M/M→A to A→M/M→A(A-parent phase,R-R phase,M-martensite),and one of Ti-50.8Ni-0.3Cr alloy change from A→R/R→A to A→R→M/M→R→A to A→R →M/M→ A to A→ M/M→ A upon cooling/heating.The R transformation temperature and M temperature hysteresis decrease,M transformation temperature increases,and R temperature hysteresis does not nearly change as about 4 ℃ for two alloys with increasing annealing temperature.更多还原