Cr-Ni-Mo系汽车齿轮钢质量稳定性水平分析

Analysis of quality stability level of Cr-Ni-Mo automotive gear steel

为了促进中国向制造业强国转型发展,制造业中关键零部件用材料在不断提升性能的同时,还必须保证具备高质量稳定性,如在推进中国高等级汽车开发时,汽车齿轮零件用材料就必须在具备高质量的同时,还具备足够的质量稳定性。Cr-Ni-Mo系齿轮钢是汽车齿轮钢中的一类重要的产品,具有承载力大、抗冲击性好的特点,应用比较广泛,因此,选择以Cr-Ni-Mo系汽车齿轮钢为研究对象开展研究。利用合金成分分析、末端淬透性试验、硬度检测、带状组织检测等试验方法,对Cr-Ni-Mo系齿轮钢冶炼成分、铸坯偏析、成品材偏析、淬透性、带状组织控制等进行研究和分析,完成了国内Cr-Ni-Mo系汽车齿轮钢先进质量稳定性控制水平研究,并分析了其对齿轮制造的影响。结果显示,国内某特钢厂Cr-Ni-Mo系汽车齿轮钢可以实现大批量工业生产时冶炼成分的精准控制,精炼终点碳质量分数波动在±0.01%以内,锰、铬、镍质量分数波动在±0.02%以内,且成品材截面碳偏析很小,碳质量分数波动不超过0.02%的炉次比例达97%。另外,该系列齿轮钢还可以达到窄淬透性带宽和低带状组织级别稳定控制,其淬透性带宽基本稳定控制在4HRC以内,带状组织稳定控制在1.5级以内,因此,国内先进Cr-Ni-Mo系汽车齿轮钢可以实现高质量、高稳定性控制,并将对重载车辆安全起到重要作用。

In order to promote the transformation and development of China towards a manufacturing power house,the materials for key components in the manufacturing industry must have high quality stability while continuously improving their performance.For example,when promoting the development of high-grade automobiles in China,the materials used for automobile gear parts must possess high quality and sufficient quality stability at the same time.The Cr-Ni-Mo gear steel is a very important product in automotive gear steel,which has the characteristics of high bearing capacity and good impact resistance,and is widely used.Therefore,the Cr-Ni-Mo automotive gear steel is taken as the research object.According to the research and analysis of the smelting composition,bloom segregation,product segregation,hardenability and band structure control of the gear steel,the advanced quality stability control level of domestic Cr-Ni-Mo automobile gear steel has been acquired,and its influence on gear manufacturing has been analyzed.The results show that the smelting composition of Cr-Ni-Mo automobile gear steel in a domestic special steel plant can be accurately controlled during industrial production.The fluctuation of C mass percent at the refining end is controlled within±0.01%,and the fluctuation of Mn,Cr,Ni mass percent is controlled within±0.02%.The C segregation in the section of finished bar is very small.The proportion of heats with C mass percent fluctuation below 0.02%reaches 97%.In addition,the narrow hardenability bandwidth and low banded structure grade can be also stable achieved.The hardenability bandwidth is basically controlled below 4HRC,and the banded structure is stably controlled below 1.5grade.Therefore,the advanced Cr-Ni-Mo automobile gear steel in China can achieve the level of high quality and high stability,and it will play an important role in the safety of heavy vehicles.