| A serial of Zn-1.0Cu-0.2Ti、Zn-1.0Cu-0.2Ti-0.1Cr Zn-1.0Cu-0.2Ti-0.05Mg alloys were parepared by melting, This eassay studied the microstructure of the alloys of different compositions with the helpofXRD、DSC、SEM. EPMA、EDS and so on, revealed the trace element alloying and heat treatment effects on alloys’mechanical properties, and alloys SCC behaviors and creep mechanism. The main results of the thesis were showed as follow:1. at room temperature, the phase composition Zn-1.0Cu-0.2Ti of alloy contained η-phase mixed with a small quantity of Cu and Ti, CuZn4-particles, and TiZn15-particles; The grain size became smaller, the minute second phase particles bigger with the addition elements Mg and Cr,; Using different heat treatment temperature and different cold to methods to improve the mechanical properties of titanium alloy copper zinc, of which230℃insulation2hours comprehensive performance is the best.2. The results show that, strain rate in the range of1×10-5s-1～8×10-7s-1,with the decrease of strain rate,the SCC susceptibility of Zn-1.0Cu-0.2Ti alloy also decreased, when strain rate at1×10~-6s-1, SCC susceptibility is the biggest, so strain rate of1×10-6s-1was adopted in the follow-up experiments. The SCC susceptibility of Zn-Cu-Ti alloy were smaller in piped water and3.5%NaCl solution compared with alloys in air; the addition elements of Mg and Cr significantly weakened the SCC susceptibility of Zn-Cu-Ti alloy,and the effect of Mg was the best.3. Zn-1.0Cu-0.2Ti alloy tensile creep variable speed rate and creep variables with the temperature and stress increased, add Cr and Mg of titanium alloy copper zinc creep resistance dramatically increase, which add the atom radius of Mg elements of the larger ZCT alloy in high stress in which has the better creep resistance. |
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