Modification of eutectic silicon and β-Al_5FeSi phases in as-cast ADC12 alloys by using samarium add

• 作 者: 饶远生 闫洪 胡志
• 机 构: Institute of Advanced Forming,Nanchang University,Jiangxi Key Laboratory for Advanced Copper and Tun
• 出 处: Journal of Rare Earths
• 发表日期: 2004年期
• 关键词: eutectic coarse modifying additions spherical Modification refinement nucleation

The effects of Sm additions(0,0.5 wt.%,1.0 wt.% and 1.5 wt.%) on the eutectic Si and β-Al5 FeSi phases of ADC12 as-cast alloys were studied by optical microscopy(OM),scanning electron microscopy(SEM) and differential thermal analysis(DTA).The experimental results showed that Sm was an effective modifying agent for the eutectic Si of ADC12 alloy,when 1.0 wt.%- 1.5 wt.% Sm was added to the alloy,the coarse acicular eutectic Si was modified into fine particle or short rod structure.Moreover,the appropriate addition of Sm(about 1.0 wt.%) had marked effects on shortening the length of needle-like β-Al5 FeSi phase.Whereas,Sm was less effective on modifying the needle-like β-iron to the Chinese script or spherical α-iron phase.The modification mechanism was also discussed.

The effects of Sm additions (0,0.5 wt.%, 1.0 wt.% And 1.5 wt.%) On the eutectic Si and β-Al5 FeSi phases of ADC12 as-cast alloys were studied by optical microscopy (OM) microscopy (SEM) and differential thermal analysis (DTA). The experimental results showed that Sm was an effective modifying agent for the eutectic Si of ADC12 alloy, when 1.0 wt.% - 1.5 wt.% Sm was added to the alloy, the coarse acicular eutectic Si was modified into fine particle or short rod structure. Moreover, the appropriate addition of Sm (about 1.0 wt.%) had marked effects on shortening the length of needle-like β-Al5 FeSi phase. Whereas, Sm was less effective on modifying the needle-like β-iron to the Chinese script or spherical α-iron phase. The modification mechanism was also discussed.