离心“蘑菇头”气缸套对石墨形态的试验影响研究

Experimental Study on the Graphite Morphology of Centrifugal “Mushroom”Cylinder Liner

对影响＂蘑菇头＂气缸套石墨组织形态的因素进行分析,采用实验优化了涂料的保温性能、浇注工艺、熔炼工艺等参数,改善缸套的金相组织形态,达到了发动机高强度、耐磨的性能要求。得到的结果：1.涂料配方：0.15~0.17%的调节剂A＋47.5%的200目石英粉＋47.5%320目石英粉＋0.25%红火山膨润土＋0.25%信阳膨润土,外加水75%~80%;2.涂料配置工艺：加入水和膨润土搅拌4个小时,再加入石英粉搅拌两个小时,再加入调节剂A搅拌十分钟,过滤加入涂料桶;3.涂料厚度在0.8~1.2mm范围内为最佳;4.来水时间为15秒,满足性能要求;5.熔炼工艺：化学成份控制：C：3.20~3.3;S：0.03~0.05;Mn：0.7~1.1;P：0.2~0.3;Cr：0.2~0.3;B：0.05~0.06;Si：2.5~2.7;炉料搭配：至少加入10%的废钢;瞬时孕育：加入0.15%~0.2%的粒度小于1毫米的75SiFe瞬时孕育。研究成果为汽车缸套的铸造生产提供了指导和借鉴作用。

This article analyzes the factors that affect the graphite morphology of the centrifugal ＂ mushroom＂ cylinder liner.By adopting the experiment of optimizing the heat preservation performance,parameters such as pouring process,melting process,the microstructure of cylinder liner of form is improved to meet the engine performance requirements of the high strength and abrasion resistance.We get the result：1.The coating formula：0.15 ~ 0.17% of the regulator A ＋ 47.5% 200 mesh quartz powder ＋ 47.5% 320 mesh quartz powder ＋ 0.25% red mountain xinyang bentonite bentonite ＋ 0.25%,adding water 75% ~ 75%;2.Coating configuration process：stir in water and bentonite for four hours,then stir in quartz powder for two hours,then stir in regulator A 10 minutes,filtering to join the bucket;3.The thickness of the coating within 0.8 ~ 1.2 mm is the best;4.The water for 15 seconds,meeting the performance requirements;5.Melting process：chemical composition control：C：3.20 ~ 3.3;S：0.03 ~ 0.05;Mn：0.7 ~ 1.1;P：0.2 ~ 0.3;Cr：0.2 ~ 0.3;B：0.05 ~ 0.06;Si：2.5 ~ 2.7;Burden collocation：at least add 10% of the scrap steel;Instantaneous inoculation：adding 0.15% ~ 0.15% of the 75 SiFe instantaneous inoculation grain size less than 1 mm.In this paper,our study provides a guidance and reference for the automotive cylinder casting production.