V-EPC制备铁基表面复合材料的表面质量和组织

Surface Quality and Microstructure of Fe Matrix Surface Composites in Vacuum-Expendable Pattern Casting(V-EPC)

以HT3 0 0为基体 ,用WC颗粒作为增强颗粒 ,通过V EPC铸渗工艺制备出较为理想的铁基表面耐磨材料 ,铸件复合层厚度均匀 ,厚度为 6mm左右 ,WC在复合层中分布较为均匀 ;在复合过程中 ,主要是铁液向复合层渗透 ,铬向母材的渗透也有 ,但量很少 ,合金层和母材的结合良好 ,属于冶金结合 ,其硬度从复合层到基体先升高后降低 ,复合层平均硬度比HT3 0 0提高 3倍左右。

Desirable WC particle reinforced HT300 matrix composites with the thickness of about 6 mm in compound layer were prepared by cast-infiltration in V-EPC, in which WC particles were distributed into the compound layer. Liquid Fe infiltrated into compound layer while a little Cr infiltrated into the matrix during cast-infiltration process. Alloying layer and the matrix belong to metallugirical bonding. The hardness of the composite decreases from the compound layer to matrix and the average hardness of the compound layer increases by about three times over that of the HT300 matrix materials.