(1. 大慶石油學(xué)院 材料科學(xué)與工程系，大慶 163318;2. 哈爾濱工業(yè)大學(xué) 材料科學(xué)與工程學(xué)院，哈爾濱 150001)
摘 要: 采用脈沖電沉積技術(shù)制備納米鎳合金及Ni/Si3N4(w)復(fù)合材料，在應(yīng)變速率為1×10−3~2×10−2 s−1，溫度為673~823 K的條件下，研究它們的超塑性拉伸變形行為，確定最佳超塑性條件并獲得最大伸長(zhǎng)率。結(jié)果表明，Ni-Co合金在773 K，應(yīng)變速率5×10−3 s−1時(shí)，最大伸長(zhǎng)率為279%；Ni/Si3N4(w)復(fù)合材料在713 K，應(yīng)變速率1×10−2 s−1時(shí)，最大伸長(zhǎng)率為635%。采用SEM 和TEM對(duì)電沉積和超塑變形前后試件的顯微結(jié)構(gòu)進(jìn)行表征。應(yīng)用晶粒長(zhǎng)大行為和協(xié)調(diào)機(jī)制對(duì)合金和復(fù)合材料的超塑性進(jìn)行對(duì)比研究和討論。
關(guān)鍵字: Ni-Co合金；低溫超塑性；脈沖電沉積
（1. Department of Materials Science and Engineering, Daqing Petroleum Institute, Daqing163318, China2. School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China）
Abstract:Abstract: A nanostructured nickel alloy and a Ni/Si3N4(w) composite were fabricated by pulse current electrodeposition, and their superplastic tensile deformation behaviors were investigated at strain rates ranging from 1×10−3 to 2×10−2 s−1 and temperatures ranging from 673 to 823 K. Optimal superplastic condition and the maximum elongation were determined. The results show that the maximum elongation of Ni-Co alloy can reach the value of 279% at strain rate of 5×10−3 s−1 and temperature 773 K, the maximum elongation of Ni/ Si3N4(w) composite is 635% at strain rate of 1×10−2 s−1 and temperature 713 K. Scanning electron microscopy and transmission electron microscopy were employed to examine the microstructures of the as-deposited and deformed samples. The superplastic behavior of the alloy and composite were compared with and discussed in terms of their grain growth behavior and accommodation mechanisms.
Key words: Ni-Co alloy; low temperature superplasticity; pulse current electrodeposition
