(1. 北京有色金屬研究總院 有色金屬材料制備加工國(guó)家重點(diǎn)實(shí)驗(yàn)室 有研億金新材料股份有限公司，北京 100088；
2. 大連理工大學(xué) 三束材料改性教育部重點(diǎn)實(shí)驗(yàn)室，大連 116024)
摘 要: 介紹了阻尼冷卻管法制備A356鋁合金半固態(tài)漿料工藝的實(shí)驗(yàn)裝置及其原理，并進(jìn)行不同澆注溫度的系列實(shí)驗(yàn)。結(jié)果表明：由于阻尼冷凝管的冷卻和攪拌作用，熔體澆注溫度越低，在兩相溫度區(qū)間內(nèi)生成的游離晶核就越多，制備得到半固態(tài)鑄件的晶粒尺寸就越小，且球化程度越高。在此實(shí)驗(yàn)原理及結(jié)果分析的基礎(chǔ)上，設(shè)計(jì)真空吸鑄−阻尼冷卻裝置，近液相線溫度的AZ91D鎂合金液在冷卻、剪切的作用下，由液態(tài)轉(zhuǎn)變?yōu)榘牍虘B(tài)漿料，然后進(jìn)入模具完成充型，實(shí)現(xiàn)鎂合金半固態(tài)漿料的制備與鑄件流變成形一體化；半固態(tài)鎂合金熔體具有觸變性及更高的黏度，以平穩(wěn)、層流的充型方式完成充型，能夠有效地改善成形件的質(zhì)量。
關(guān)鍵字: 阻尼冷卻管法；真空吸鑄工藝；半固態(tài)漿料；流變成形；顯微組織
aluminum and magnesium alloys semisolid slurry
（1. State Key Laboratory of Nonferrous Metals and Process, GRIKIN Advanced Materials Co., Ltd.,
General Research Institute for Nonferrous Metals, Beijing 100088, China)
(2. Key Laboratory for Materials Modification by Laser, Ion and Electron Beams, Ministry of Education,
Dalian University of Technology, Dalian 116024, China）
Abstract:The setup and principle of damper cooling tube (DCT) process, which is used to prepare semisolid slurry of A356 aluminum alloy in different pouring temperatures, were introduced. The results show that the microstructures are directly related to the pouring temperature, the lower pouring temperature is, the more stray nuclei produced are, the smaller grain size is and the bigger shape factor is. On the basis of the experimental results and principle, a novel semisolid processing technique, called vacuum suction casting-damper cooling tube (VSC-DCT) process, is used to manufacture high quality components of AZ91D Mg-alloy directly from a near-liquidus metal. The outstanding feature of this investigation is attributed to the fact that the VSC-DCT process combines the semi-solid slurry making and component forming operation into one step, therefore, eliminating the need for specially prepared slurry and subsequent slurry transportation steps. The semisolid metal with higher viscosity can be caused to fill the mold with solid-front fill, and the surface quality of the sheets fabricated by the VSC-DCT method is improved significantly.
Key words: damper cooling tube method; vacuum suction casting; semisolid slurry; rheoforming; microstructure
