【摘要】：近年來,隨著國家電力技術(shù)的進步,我國真空開關(guān)有了飛躍的發(fā)展,對其核心部件觸頭材料提出了更高的要求,CuCr觸頭材料是目前國內(nèi)外真空開關(guān)的首選材料,需開發(fā)研制新型CuCr觸頭材料,以滿足更嚴苛環(huán)境下的使用要求。研究發(fā)現(xiàn)CuCr合金的微觀特性對其宏觀性能有重要的影響。目前,改善CuCr觸頭材料組織性能的主要方法有:1.添加新組元,優(yōu)化合金成分;2.改進和采用新工藝;3.后續(xù)加工及熱處理。本論文采用高能預(yù)球磨細化Cr粉,并利用先進的熱等靜壓技術(shù)制備CuCr觸頭材料,添加Zr和TiC,并后續(xù)進行固溶時效熱處理,研究Cr顆粒尺寸、添加組元和熱處理對CuCr觸頭材料微觀組織、維氏硬度、電導(dǎo)率、機械強度和真空電擊穿性能的影響。通過分析CuCr觸頭材料的組織及性能可知:采用100(TC*120MPaa*2h熱等靜壓固相燒結(jié)工藝可成功制備不同Cr顆粒尺寸接近完全致密的CuCr觸頭材料,合金的組織均勻致密,物相純凈。添加的Zr存在于Cu基體,并在Cu/Cr界面富集,改善Cu與Cr的燒結(jié)性;添加的TiC存在于Cu基體中,填充Cu與Cr的間隙。結(jié)果表明:添加TiC組元,合金的機械性能增加,電導(dǎo)率略有降低;隨著Cr顆粒尺寸的減小,合金的機械性能提高,電導(dǎo)率有一定程度的降低;采用960℃*1h+50℃*4h固溶時效工藝,合金的機械性能明顯提高,電導(dǎo)率有一定程度的回升。對CuCr觸頭材料的電擊穿燒蝕研究表明,其電擊穿發(fā)生在富Cr相及富Cr相與富Cu相的邊界。減小Cr顆粒尺寸,電擊穿也會發(fā)生在富Cu相上,CuCr合金耐電壓強度提高,截流值降低,電弧壽命略有延長。添加TiC,電擊穿發(fā)生在電子逸出功較低的TiC上以及TiC/Cu相界面處,電弧得到有效的分散,合金耐電壓強度提高,截流值降低,電弧壽命延長;經(jīng)過固溶時效處理,合金燒蝕區(qū)域較分散,耐電壓強度提高,截流值降低,電弧壽命延長。CuCr29Zr1(Cr76μm)合金的相對電導(dǎo)率為44.76%IACS,抗拉強度357.0MPa,耐電壓強度5.38×107V/m,截流值為4.04A;CuCr28Zr1TiCl(Cr76μm)合金相對電導(dǎo)率為40.17%IACS,抗拉強度達到374.3MPa,耐電壓強度7.69×107V/m,截流值為3.80A;CuCr28Zr1TiCl(Cr10-15μm)合金相對電導(dǎo)率為 33.60%IACS,抗拉強度達到 400.7MPa,耐電壓強度12.6×107V/m,截流值為3.14A。
[Abstract]:In recent years, with the progress of national power technology, the vacuum switch in China has made a leap development. A higher requirement for the contact material of its core component is put forward. CuCr contact material is the first choice material of vacuum switch at home and abroad at present. A new type of CuCr contact material should be developed to meet the requirements of more severe environment. It is found that the microcosmic properties of CuCr alloys have an important effect on their macroscopic properties. At present, the main methods to improve the microstructure and properties of CuCr contact materials are: 1. 1. Adding new component to optimize alloy composition. Improve and adopt the new process. Follow-up processing and heat treatment. In this paper, Cr powder was refined by high-energy pre-milling, and CuCr contact materials were prepared by advanced hot isostatic pressing technology, Zr and tic were added, and the grain size of Cr was studied by solution aging heat treatment. Effects of addition and heat treatment on microstructure, Vickers hardness, electrical conductivity, mechanical strength and vacuum breakdown properties of CuCr contact materials. By analyzing the microstructure and properties of CuCr contact materials, it can be concluded that CuCr contact materials with different Cr particle sizes close to complete density can be successfully prepared by using 100 (TC*120MPaa*2h) hot isostatic pressure solid-state sintering process. The microstructure of the alloy is uniform and dense, and the phase is pure. The addition of Zr exists in Cu matrix and is enriched at the interface of Cu/Cr to improve the sintering properties of Cu and Cr, and the added TiC exists in Cu matrix to fill the gap between Cu and Cr. The results showed that the mechanical properties of the alloy increased and the electrical conductivity decreased slightly with the addition of TiC component, and the mechanical properties of the alloy increased with the decrease of Cr particle size, the electrical conductivity decreased to a certain extent, and the process of solution aging at 960 鈩，

本文編號：2169809