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pISSN : 1598-706X / eISSN : 2288-8381


(논문)연구논문

한국주조공학회지 (4권2호 96-101)

Study on the effect of silicon content on matrix of hypo-eutectic Cr alloyed cast iron

아공정(亞共晶)Cr 주철(鑄鐵)의 기지조직(基地組織)에 미치는 Si의 영향(影響)

Sug-Won KIM, Oh-Yeon LEE, Dong-Keon KIM

Chonbuk National University

Abstract

The morphologies of eutectic cell formed during solidification affect on the mechanical properties in high Cr cast iron. In order to investigate the influence of Si on the structure, five kinds of specimen containing 16.42% Cr with varying amount of Si (0.51%, 1.17%, 2.22%, 2.71%, 3.56%) were poured into shell mould preheated 330℃ at 1510℃. The effect of Si on matrix in hypo-eutctic Cr cast iron (2.48% C, 16.42%) were studied through its mechanical tests and observation of microstructure using of metallurgical microscope, EPMA, SEM and Image analyzer systematically. The results obtained from the above studies are as follows: 1. Because of △T decreasing with increasing Si content, the morpologies of colony change into uniform bar-type carbide from plate-type ones, moreover eutectic colony size (Ew) becomes narrow and spacing of carbide wider. 2. As Si content increases, the amount of carbides also increases and most of Cr were dissolved in carbides while Si in matrix. 3. The hardness, tensile strength and wear resistance were increasing while impact value decreased with increasing Si content. 4. In fracture section, small amount of dimple pattern was observed in less than 1.17% Si but more than 2.22% Si river pattern was presented.

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