(中南大學 輕質(zhì)高強結(jié)構(gòu)材料國家級重點實驗室，長沙 410083)
摘 要: 以90W-7Ni-3Fe預混粉末和30CrMnSiNi2A鋼霧化粉末為原料，采用熱等靜壓技術(shù)在1350 ℃、150 MPa、3 h燒結(jié)工藝下進行共燒結(jié)。利用SEM、XRD、TEM和萬能力學試驗機等研究了90W-7Ni-3Fe/ 30CrMnSiNi2A共燒結(jié)體的微觀組織和力學性能特征。結(jié)果表明：采用共燒結(jié)方法成功制備了90W-7Ni-3Fe/30CrMnSiNi2A結(jié)構(gòu)復合材料，共燒結(jié)體組織均勻、致密度高、界面無孔洞和裂紋，結(jié)合良好；鎢合金和鋼基體的相對密度均大于99%，抗拉強度分別為920 MPa和1309 MPa。在鎢合金和鋼的界面區(qū)域發(fā)生強烈的元素擴散，形成了厚度為40~50 μm的Fe6W6C相，并分析了Fe6W6C相的形成；硬脆Fe6W6C相的存在惡化鎢合金/鋼界面的力學性能，界面的抗拉強度為85 MPa。斷裂模式為Fe6W6C相和W相的混合斷裂。
關(guān)鍵字: 鎢/鋼結(jié)構(gòu)復合材料；熱等靜壓；粉末共燒結(jié)；微觀組織；力學性能
（National Key Laboratory of Science and Technology for National Defence on High-strength Structural Materials, Central South University, Changsha 410083, China）
Abstract:90W-7Ni-3Fe premixed powders and 30CrMnSiNi2A steel atomized powder were used as raw materials and co-sintered by HIP at (1350 ℃, 150 MPa, 3 h). The SEM, XRD, TEM and universal mechanical testing machine were used to evaluate the microstructure and mechanical properties of co-sintered samples. The results show that the 90W-7Ni-3Fe/30CrMnSiNi2A composite can be successfully fabricated by co-sintering method. The co-sintered samples shows high density and uniform microstructure, and the interface present good metallurgical bonding free from voids or cracks. The relative densities of 90W-7Ni-3Fe alloy and steel are more than 99%, and their tensile strengths are 920 MPa and 1309 MPa, respectively. The violent element reaction occurs at the interface between 90W-7Ni-3Fe alloy and 30CrMnSiNi2A steel and the Fe6W6C phase with thickness of 40-50 μm forms. In addition, the formation mechanism of Fe6W6C phase was discussed based on the phase diagram theory. The tensile strength of tungsten alloy/steel joint is 85 MPa, and the tungsten/steel composites failed mainly along the interface of tungsten alloy/Fe6W6C, which show Fe6W6C phase brittle fracture and W/W interfacial failure on the fracture.
Key words: tungsten/steel structural composite materials; hot isostatic pressing; co-sintering; microstructure; mechanical property
