(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: 以h-BN、石墨、短切炭纖維和樹(shù)脂等為原料，采用模壓技術(shù)+浸漬/炭化技術(shù)制備4種C/C-BN復(fù)合材料，并在M2000型試驗(yàn)相同測(cè)試其與40Cr鋼配副時(shí)的滑動(dòng)摩擦性能。結(jié)果表明：h-BN質(zhì)量分?jǐn)?shù)分別為 3.4%和20.7%的材料的抗壓強(qiáng)度較高，其摩擦因數(shù)隨載荷增加均先增加后降低；h-BN為6.8%的材料的摩擦因數(shù)降幅最大，達(dá)0.049；而h-BN為10.1%的材料的抗壓強(qiáng)度最低，其摩擦因數(shù)呈現(xiàn)波浪狀起伏。隨載荷增加, h-BN為3.4%和20.7%的材料的體積磨損增幅較低；而h-BN為6.8%的材料的體積磨損增幅最大，達(dá)2.41 mm3。隨著時(shí)間的延長(zhǎng)，4種材料的摩擦因數(shù)均逐漸穩(wěn)定。SEM觀察表明：h-BN為3.4%的材料的摩擦表面在中低載荷下較完整致密、但有長(zhǎng)度與石墨微晶尺寸接近(10~50 µm)的網(wǎng)絡(luò)狀裂紋，摩擦表面在高載荷下則較粗糙；而h-BN為10.1%的材料的摩擦表面均較粗糙、不完整。
關(guān)鍵字: C/C-BN復(fù)合材料；h-BN；摩擦磨損
（State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:Four kinds of C/C-BN composites were prepared by mould pressing combined with impregnation and carbonization of furan resin using h-BN powder, graphite powder, short-cut PAN carbon fiber and resin as greed material. The sliding friction behaviors of the C/C-BN composites against 40Cr steel ring were conducted on M2000 tester. The results show that composites with 3.4% or 20.7% (mass fraction) h-BN hold high compressive strength, their friction coefficients increase at first and then decrease with the increase of the testing loads. The friction coefficient of composites with 6.8% h-BN holds the largest decreasing range, which reaches 0.049, while the composites with 10.1% h-BN have the lowest strength and wave-like fluctuated friction coefficient with the increase of the loads. The composites with 3.4% or 20.7% h-BN remain hold low and stable volume wear loss with the increase of the loads. The composites with 6.8% h-BN hold the highest volume wear loss to 2.41 mm3. SEM observation shows that the wear surfaces of composites with 3.4% h-BN are integrate and compact at low and middle loads except some net-shape micro-cracks with the length of 10−50 µm, but it become very rough at high load. The worn surfaces of composites with 10.1% h-BN are very rough and un-integrated under the testing loads.
Key words: C/C-BN composite material; h-BN; friction and wear
