SiMoCr CGI (compacted graphite iron) has the potential to be a cost-effective replacement for some hot working tool steel parts like shot sleeve in HPDC (High-Pressure Die Casting) applications. Thermal fatigue testing of SiMoCr CGI cast alloy was performed on Gleeble 1500D machine. Cracks were evaluated on non-nitrided and nitrided samples at test temperatures of 400 and 600 °C, after 1000, 2000 and 4000 thermal cycles. Samples were heated to prescribed test temperature and afterward cooled in computer-guided cycles. After the test, all the samples were axially and radially sectioned and cracks on cross sections were evaluated. Length of all cracks which occurred was measured and statistically evaluated, i.e., the average length of cracks and distribution of crack lengths were determined. At nitrided samples, higher values for average crack lengths were obtained while density of cracks was lower in comparison with non-nitrided samples.

中文翻译：

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用于HPDC工具的SiMoCr压缩石墨铸铁的热疲劳测试

SiMoCr CGI（压缩石墨铁）有可能成为HPDC（高压压铸）应用中某些热加工工具钢零件（如喷丸套筒）的经济高效替代品。SiMoCr CGI铸造合金的热疲劳测试是在Gleeble 1500D机器上进行的。经过1000、2000和4000次热循环后，在400和600°C的测试温度下评估了非氮化和氮化样品的裂纹。将样品加热到规定的测试温度，然后在计算机引导的循环中冷却。试验后，将所有样品轴向和径向切开，并评估横截面上的裂纹。测量并统计评估所有出现的裂纹的长度，即确定平均裂纹长度和裂纹长度分布。在氮化样品中