摘要
原砂的粒度分布是影响型砂的工艺性能及铸件表面质量的重要因素之一.而目前我国铸造行业使用的原砂仍处在自然分布状态,所以生产的铸件表面质量较差,如铸钢件表面粗糙度 Ra 值一般都在50μm-100μm之间.本文探讨了原砂粒度分布对型砂透气性、强度及铸件表面粗糙度的影响.又对级配砂工艺进行了实验研究,把原砂筛分成单筛砂,然后用正交设计法确定各种粒度砂子的最佳加入量.通过实验得出了最佳级配砂比例.利用级配砂浇注的铸钢件可使表面粗糙度Ra 值提高一级,即由50μm-100μm提高到25μm-50μm.
Origional sand used in our country's foundry trade is still in natural state today,and sur- face quality of casting is fairly poor.For example,cast steel roughness Ra is 50μm-100μm.It turned out that origional sand distribution is one of the important factors which affect moulding sand's processing property and cast surface quality.The effect of origional sand's grain size distribution on moulding sand permeabity,strength and cast roughness was studied in this paper.Origional sand was first screened into single screen sand,and then the best added quantity of different kinds of size sands was determined,and the est optimun grade sand propor tion was got by orthogonal experiments.Cast steel roughness Ra can be in a grade by using grade sand casting,i.e.Ra increases from 50μm-100μm to 25μm-50μm.
关键词
型砂
粒度
铸件
级配
表面粗糙度
grade
optimization
grain size distribution
cast roughness
