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


(논문)연구논문

한국주조공학회지 (20권4호 269-276)

Microstructural and Mechanical Characteristics of A356 Alloy Cast by Semi-Solid Squeeze Process

반응고 공정 가압 주조한 A356합금의 미세조직 및 기계적 특성

Sug-Won Kim, Yeun-Cheul Kang, Dong-Kun Kim, Sinji Kumai*

Chonbuk National Universit, *Tokyo Institute of Technology

Abstract

So far, the study on semi-solid process has been carried out to develop and research new advanced materials without some casting defects. In this study, A356 billets consisted of various dendritic shapes were prepared using electro- magnetic stirring process continuously. As-cast respectively has liquidus temperature of 625.6℃ and solidus temperature of 573.55℃ A356 slugs were reheated homogeneously at different temperatures of 580, 590 and 605℃, followed by squeezing in a mold insulated with applied pressures(0, 25, 50 and 70 MPa). In order to investigate on aging responce for casts, 50 MPa squeezed specimen among all specimens was prepared in aging treatments, which conditions are aging temperature of 160℃ and holding times of 0, 45, 90, 270, 360, 720, 1440 and 2880 min after solution treatment (540℃ for 10 hr). SSM ingot with the output velocity of 150mm/min appeared more spheroidal shape and fine structure than that with the output velocity of 250 mm/min. According to increasing in reheating temperature, numbers of fatigue cycles, U.T.S and elongation increased at same time.

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