CAJ | 학술논문

对不同工艺处理的铝硅合金ZAlSi7Cu4用自约束型热疲劳实验机进行20?300℃、20?350℃和20?400℃的热循环试验,研究不同处理工艺对该材料热疲劳性能的影响及不同温度幅对裂纹生长的影响.通过光学显微镜和扫描电镜观察试样的热疲劳裂纹形貌,研究合金热疲劳损伤机制.结果表明:该合金经过T6处理后比其他两种方式处理的合金具有更好的热疲劳性能;颗粒的位向会影响裂纹的扩展路径;在下限温度不变的情况下,随着上限温度的提高,ZAlSi7Cu4的3种状态合金的寿命都缩短.当下限温度为20℃时,合金在上限温度为300~350℃区间内的温度敏感性高于其在上限温度为350~400℃区间内的温度敏感性.
대불동공예처리적려규합금ZAlSi7Cu4용자약속형열피로실험궤진행20?300℃、20?350℃화20?400℃적열순배시험,연구불동처리공예대해재료열피로성능적영향급불동온도폭대렬문생장적영향.통과광학현미경화소묘전경관찰시양적열피로렬문형모,연구합금열피로손상궤제.결과표명:해합금경과T6처리후비기타량충방식처리적합금구유경호적열피로성능;과립적위향회영향렬문적확전로경;재하한온도불변적정황하,수착상한온도적제고,ZAlSi7Cu4적3충상태합금적수명도축단.당하한온도위20℃시,합금재상한온도위300~350℃구간내적온도민감성고우기재상한온도위350~400℃구간내적온도민감성.
The casting silumin ZAlSi7Cu4 that was treated with different technologies for heating processing was used to make a thermal cycle experiment at 20?300 ℃, 20?350 ℃ and 20?400 ℃, respectively, on a self-restrict thermal fatigue experimental machine. The effect of thermal fatigue property caused by different technologies for heating processing and the effect of crack growth caused by different temperature breadths were studied. Optica1 microscopy (OM) and scanning electron microscopy (SEM) were used to examine the damage mechanisms of thermal fatigue. The results show that the sample with T6 treatment has better property than other two kinds of samples. The expansion path of crack can be influenced by the location of grains. With the increase of the maximum temperature, the lifespan of three kinds of alloys will decrease when the minimum temperature is fixed. In the interval of 300?350 ℃, the temperature sensitivity of the alloy is higher than that in the interval of 350?400 ℃ when the minimum temperature keeps at 20 ℃.