Al-Cu-Mn주조합금의 SCC특성에 미치는 Cd첨가의 영향

이찬희; 김경현; 김인배; Chan-Hee Lee; Kyung-Hyun Kim; In-Bae Kim

Korean Journal of Materials Research, Vol.11, No.4, 266-271, April, 2001

Export Citation

Al-Cu-Mn주조합금의 SCC특성에 미치는 Cd첨가의 영향

The Mechanical Properties of CFRC under High Temperature

이찬희, 김경현¹, 김인배

부산대학교 금속공학과
¹한국기계연구원

Chan-Hee Lee, Kyung-Hyun Kim¹, and In-Bae Kim

Department of Metallurgical Engineering, Pusan National University, Pusan 609-735, Korea
¹Dept. of Materials Eng., Korea Institute of Machinery and Materials, Changwon 641-010, Korea

초록

Al-Cu-Mn 주조합금의 응력부식균열 저항성에 미치는 Cd첨가의 영향을 C-ring test와 전기전도도 시험을 통하여 조사하였다. Cd첨가량이 증가함에 따라 전기전도도가 증가하였고 SCC 저항성도 증가하였다. SCC 시험결과 균열이 입계를 따라 전파되는 입계파괴가 일어났으며, 파면은 취성파괴양상을 나타내었고, 입계를 따라 조대 석출물과 무석출대가 나타난 것으로 보아서 이 합금의 SCC 기구는 anodic dissolution model이라고 판단된다. Cd을 첨가하지 않은 경우 최대경도값은 127Hv였으나, Cd을 첨가한 경우 최대경도값은 138∼146Hv로 증가하였다.

Effect of Cd addition on the stress corrosion cracking(SCC) resistance of Al-Cu-Mn cast alloy was investigated by C-ring test and electrical conductivity measurement. With increasing Cd contents, the electrical conductivity and the SCC resistance were increased. The PFZ and coarse precipitates along the grain boundary were observed from TEM micrographs. The fracture made of the alloys was confirmed as intergranular type and showed brittle fracture surface. As a result, it was concluded that the SCC mechanism of these alloys is the anodic dissolution model. The maximum hardness was increased from 127Hv in the Cd-free alloy to 138∼145Hv in the Cd addition alloys.

Keywords:Al-Cu-Mn cast alloy;SCC resistance;Intergranular fracture. Anodic dissolution model

[References]

Wilm A, Metallurgie, 8, 225 (1906)
Polmear IJ, Mater. Trans., 37, 12 (1996)
박정규, 김경현, 이태호, 김인배, 대한금속학회지, 37, 142 (1999)
MIL-H-6088G, 'Heat Treatment of Aluminum Alloys', p. 43 (1991) (1991)
SAE AMS 4107A (1986) (1986)
Beddoes JC, Demalherbe MC, Can. Aeronaut. Space, 27, 222 (1981)
Hono K, Sakurai T, Polmear IJ, Scripta Metall., 30, 695 (1994)
Muddle BC, Polmear IJ, Acta Metall., 37, 777 (1989)
Islam MU, Wallace W, Met. Tech., 11, 320 (1984)
Sanders TH, Jr, Ludwiczak EA, Sawtell RR, Mater. Sci. Eng., 43, 247 (1980)
Nicholson RB, J. Inst. Met, 95, 91 (1967)
De Ardo AJ, Townsend RD, Metall. Trans., 1, 2573 (1970)
Green JA, Novak DL, Metall. Trans., 4, 1922 (1973)
Poulose PK, Morral JE, McEvily AJ, Metall. Trans., 5, 1393 (1974)

[Referenced By]

[1] Wilm A, Metallurgie, 8, 225 (1906)

[2] Polmear IJ, Mater. Trans., 37, 12 (1996)

[3] 박정규, 김경현, 이태호, 김인배, 대한금속학회지, 37, 142 (1999)

[4] MIL-H-6088G, 'Heat Treatment of Aluminum Alloys', p. 43 (1991) (1991)

[5] SAE AMS 4107A (1986) (1986)

[6] Beddoes JC, Demalherbe MC, Can. Aeronaut. Space, 27, 222 (1981)

[7] Hono K, Sakurai T, Polmear IJ, Scripta Metall., 30, 695 (1994)

[8] Muddle BC, Polmear IJ, Acta Metall., 37, 777 (1989)

[9] Islam MU, Wallace W, Met. Tech., 11, 320 (1984)

[10] Sanders TH, Jr, Ludwiczak EA, Sawtell RR, Mater. Sci. Eng., 43, 247 (1980)

[11] Nicholson RB, J. Inst. Met, 95, 91 (1967)

[12] De Ardo AJ, Townsend RD, Metall. Trans., 1, 2573 (1970)

[13] Green JA, Novak DL, Metall. Trans., 4, 1922 (1973)

[14] Poulose PK, Morral JE, McEvily AJ, Metall. Trans., 5, 1393 (1974)