(1. 河南科技大學(xué) 材料科學(xué)與工程學(xué)院，洛陽 471023；
2. 有色金屬共性技術(shù)河南省協(xié)同創(chuàng)新中心，洛陽 471023)
摘 要: 采用真空熱壓燒結(jié)-內(nèi)氧化法制備Al2O3-Cu/(25)W(5)Cr和Al2O3-Cu/(35)W(5)Cr電觸頭材料，分別測試其致密度、導(dǎo)電率和布氏硬度；利用場發(fā)射掃描電鏡分析觸頭材料的微觀組織；利用JF04C電接觸觸點(diǎn)測試系統(tǒng)研究兩種觸頭材料的電接觸性能。結(jié)果表明：納米Al2O3顆粒釘扎位錯(cuò)引起位錯(cuò)纏結(jié)；在電弧侵蝕過程中，Al2O3-Cu/(25)W(5)Cr觸頭在30 A時(shí)有少部分材料從陽極轉(zhuǎn)移至陰極，但兩種觸頭材料最終的質(zhì)量轉(zhuǎn)移方向都是從陰極轉(zhuǎn)移到陽極；電弧侵蝕過程中隨著Cu的熔化、蒸發(fā)和噴濺，W顆粒逐漸聚集并形成針狀的骨架，陽極形成了凸起，陰極留下灼坑；當(dāng)彌散銅基體中W 的含量從25%增加至35%(質(zhì)量分?jǐn)?shù))時(shí)，觸頭的熔焊力下降，抗熔焊性能提高。
關(guān)鍵字: 真空熱壓燒結(jié)；電接觸；電弧侵蝕；材料轉(zhuǎn)移；熔焊力
（1. School of Materials Science and Engineering, Henan University of Science and Technology, Luoyang 471023, China;
2. Collaborative Innovation Center of Nonferrous Metals, Luoyang 471023, China）
Abstract:The Al2O3-Cu/(25)W(5)Cr and Al2O3-Cu/(35)W(5)Cr composites were prepared by vacuum hot-pressing sintering and internal oxidation methods. Their relative density, electrical conductivity and Brinell hardness were measured, respectively. The microstructure was analyzed by scanning electron microscope. The JF04C electrical contact testing system was used to investigate the welding force and electric contact performance. The results shows that the pining effect of nano-Al2O3 particles causes tangle and intersecting of dislocations. The Al2O3-Cu/(25)W(5)Cr contact has a little mass transfer from the anode to cathode. But the final mass transfer direction of the two composites is from the cathode to anode. With the melting, evaporation and sputtering of Cu, W particles gathers and transforms into needle-shaped skeleton. Finally, pip and crater are presented on the anode and cathode surface, respectively. When the content of W in the dispersed copper matrix increases from 25% to 35% (mass fraction), the welding force reduces obviously.
Key words: hot-pressing sintering; electrical contact; arc erosion; material transfer; welding force
