D、E型石墨灰铁连铸管在曲轴衬套上的应用

Application of Type D&E Grey Iron Tube Made by Continuous Cast in Crankshaft Bushing

论证了用水平连铸灰铁棒材制作曲轴衬套时,一个常见缺陷产生的由来,指出:衬套内孔上部分弧段较软的原因在于,棒材横断面上有偏心分布的"液芯组织",这种等轴晶组织石墨粗大,铁素体含量多,无论是在铸态还是经淬火处理,其硬度和耐磨性均低于先行凝固的外壳层。用垂直连续铸造方法拉制出灰铁空心型材,全断面上的石墨形态为D、E混合型,用来制作新型内燃机的曲轴衬套,表现出良好的机械性能和理想的服役寿命。

A common defect is demonstrated when the crankshaft bushing made by horizontal contin- uous cast grey iron bar. The reason that part of inner bore of bushing is softer lies in the eccentric distribution of ＂liquid core structure＂ on the cross - section of solid bar. The graphite of this isometric crystal structure is coarse and with higher percent of ferrite. Either as cast or quenched, its＇ hardness and wear resistance are lower than outer shell solidified. On the full section of grey iron tube made by vertical con- tinuous cast, the graphite is mixed type of D＆E. It could be used in crankshaft bushing for new type of combustion engine, which will achieve good mechanical performance and ideal working life.