(昆明理工大學(xué) 材料科學(xué)與工程學(xué)院昆明 650093)
摘 要: 采用軋制-重熔應(yīng)變誘導(dǎo)熔化激活法(SIMA)制備半固態(tài)漿料并進(jìn)行反擠壓成形制備不同成形階段的銅合金軸套零件，研究銅合金半固態(tài)反擠壓成形過程中的組織演變和偏析行為。結(jié)果表明：半固態(tài)ZCuSn10P1銅合金組織主要由α-Cu相、Cu41Sn11(δ)相、Cu3P相和Cu13.7Sn(β′)相組成，半固態(tài)反擠壓過程中漿料由型腔底部向端部充型，產(chǎn)生明顯的固-液偏析；隨著半固態(tài)ZCuSn10P1銅合金成形的進(jìn)行，固-液偏析傾向減小，組織缺陷減少，當(dāng)完全成形時組織中無明顯缺陷，晶粒圓整度較好且分布均勻；半固態(tài)反擠壓成形ZCuSn10P1銅合金組織中微觀元素偏析傾向嚴(yán)重，Sn、P元素在晶間和晶內(nèi)液島富集，而在α-Cu基體中含量較少。隨著半固態(tài)銅合金成形的進(jìn)行，半固態(tài)ZCuSn10P1銅合金中Sn元素偏析現(xiàn)象加劇，完全成形時，其偏析程度有所減小，但相同類型區(qū)域元素的均勻性較差。
關(guān)鍵字: 半固態(tài)；銅合金；組織演變；偏析行為；擠壓成形
（Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming 650093, China）
Abstract:The semi-solid slurry was prepared by rolling remelting strain induced melting activation method (SIMA), and the copper alloy shaft sleeve parts at different forming stages were prepared by back extrusion. The microstructure evolution and segregation behavior of copper alloy during semi-solid back extrusion were studied. The results show that the phase structure of semi-solid ZCuSn10P1 copper alloy is mainly composed of α-Cu phase, Cu41Sn11 (δ) phase, Cu3P phase and Cu13.7Sn (β′) phase. During the semi-solid extrusion process, the slurry is filled from the bottom of the cavity to the end, and obvious solid-liquid segregation occurs during the forming process. The tendency of solid-liquid segregation and structural defects decrease with the semi-solid ZCuSn10P1 copper alloy forming. When the semi-solid extrusion is fully formed, there is no obvious defects in the structure, and the grain roundness is high and the grain distribution is uniform. The segregation of micro elements is serious in the microstructure of semi-solid extruded copper alloy, and Sn and P elements are enriched in intergranular and intragranular liquid islands, while the content of Sn and P elements in the matrix is less. With the semi-solid ZCuSn10P1 copper alloy forming, the segregation of Sn element in semi-solid copper alloy intensifies. The segregation degree decreases when the semi-solid ZCuSn10P1 copper alloy is fully formed, but the element homogeneity in the same type of area is poor.
Key words: semi-solid; copper alloy; microstructure evolution; segregation behavior; extrusion forming
