(中南大學(xué) 粉末冶金國(guó)家重點(diǎn)實(shí)驗(yàn)室，長(zhǎng)沙 410083)
摘 要: 研究90W-7Ni-3Fe高密度合金的微波燒結(jié)工藝，探討燒結(jié)溫度和燒結(jié)時(shí)間等工藝參數(shù)對(duì)合金密度和力學(xué)性能的影響，并對(duì)W晶粒的生長(zhǎng)規(guī)律進(jìn)行分析。結(jié)果表明：該合金的微波燒結(jié)升溫速度快，燒結(jié)周期短；微波燒結(jié)促進(jìn)合金固結(jié)，在1 480 ℃，5 min條件下，獲得相對(duì)密度為99.24%、拉伸強(qiáng)度為925 MPa和伸長(zhǎng)率為23.64%的樣品；在短時(shí)間內(nèi)燒結(jié)時(shí)，微波燒結(jié)樣品的W晶粒尺寸小于常規(guī)燒結(jié)的，但微波燒結(jié)樣品的生長(zhǎng)速率更快，微波燒結(jié)不宜過度延長(zhǎng)燒結(jié)時(shí)間。
關(guān)鍵字: W-Ni-Fe合金；微波燒結(jié)；晶粒生長(zhǎng)
（State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:90W-7Ni-3Fe heavy alloys was preliminarily sintered via microwave radiation, and the effects of sintering parameters, such as peak temperature and sintering time on the density and mechanical performance of alloy were investigated, the grain growth of W was analyzed. The results show that the heating rate of the alloy by microwave sintering technique is fast, therefore the sintering cycle reduces dramatically. The consolidating process is promoted and the as-sintered alloys have excellent properties, such as relative density of 99.24%, tensile strength of 925 MPa and elongation of 23.64% after sintering at 1 480 ℃ for 5 min. In spite of higher growth rate microwave sintering leads to finer W grain size after short time soaking, compared with conventional sintering, which suggests that microwave sintering leads to higher growth rate of W grains, and the prolongation of sintering time of W in heavy alloys is undesirable.
Key words: W-Ni-Fe alloy; microwave sintering; grain growth
