铸造低铬磨球早期失效的研究

Research on Early Failure of Low Chromium Cast Grinding Balls

通过对低铬磨球进行落球试验和凿击试验,得出：采用金属型-砂型复合铸型铸造的低格磨球早期失效成梨形前,大量磨球存在剥落现象;裂纹首先产生于金属型砂型交界部位,而后产生碎片剥落,且碎片是从金属型砂型交界部位剥离;对剥落碎片的断口形貌分析,可判断金属型砂型处磨球碎片的断裂方式为解理穿晶脆性断裂。

Through the falling test and chiseling-hammering test conducted with the metal-sand composite mould cast low Cr grinding balls, it was concluded that peeling phenomenon had occurred with many balls before their early failure.The cracking initiated at the area of interface between the metal mould and sand mould, then the debris peeling occurred, and the debris peeled from the area of metal-sand interface of the composite mould.By analyzing the fracture morphology of the peeled debris, it was considered that the fracture type of ball debris at metal-sand mould interface was of the grain-through brittle cleavage fracture.