(中南大學(xué) 輕質(zhì)高強結(jié)構(gòu)材料國防科技重點實驗室，長沙 410083)
摘 要: 以電解銅粉、酚醛樹脂包覆短碳纖維為原料，通過球磨混合，冷壓成型及加壓燒結(jié)工藝制備碳纖維分散均勻、結(jié)構(gòu)可調(diào)控、性能良好、工藝簡單、成本低的短碳纖維/銅復(fù)合材料。對比分析球磨2 h、3 h、4 h后短碳纖維在基體中的形貌及結(jié)構(gòu)變化、均勻分布程度，短碳纖維/銅復(fù)合材料的顯微組織及其物理和力學(xué)性能的差異。結(jié)果表明：在樹脂對短碳纖維的分散和保護作用下，碳纖維在銅基體中的分散均勻性得到較大提高，碳纖維/銅復(fù)合材料內(nèi)部碳/銅界面結(jié)合良好且基體均較為致密；隨著球磨時間的延長，碳纖維只發(fā)生形貌及長度的變化而不發(fā)生結(jié)構(gòu)改變，長度分布的均一化程度逐漸提高，碳纖維平均長度由32.28 mm逐漸減小至23.65 mm；短碳纖維/銅復(fù)合材料的表觀密度、電導(dǎo)率、抗彎強度先增加后減小，開孔率隨球磨時間的增加先減小后增大，硬度無明顯變化。球磨分散3 h制備的短碳纖維/銅復(fù)合材料的綜合物理和力學(xué)性能良好，其表觀密度、開孔率、電導(dǎo)率、抗彎強度、硬度分別為7.93 g/cm3、4.53%、38.73 MS/m、332.94 MPa、46.17 HV。
關(guān)鍵字: 樹脂包覆短碳纖維；球磨分散；調(diào)控；顯微組織；物理性能；力學(xué)性能
（National Key Laboratory of Science and Technology for National Defence on High-strength Structural Materials, Central South University, Changsha 410083, China）
Abstract:Using electrolytic copper powder and phenolic resin-coated short carbon fiber as raw materials, the SCF/Cu composites with short carbon fiber uniform dispersed, controllable structure, good performance, simple process and low cost were prepared through ball mill mixing, cold pressing and pressure sintering. The morphology and structural changes, the uniform distribution degree of short carbon fiber in the matrix after ball milling for 2 h, 3 h, and 4 h, as well as the differences in microstructure, physical and mechanical properties of the SCF/Cu composites were compared and analyzed. The results show that the dispersion uniformity of short carbon fiber in copper matrix is greatly improved under the effect of phenolic resin on dispersion and protection of short carbon fiber, the carbon/copper interface is well bonded and the matrix is dense in the SCF/Cu composites. With the increase of ball milling time, only the morphology and length of short carbon fiber change without structural change. The uniformity of length distribution gradually increase, and the average length of the short carbon fiber gradually decrease from 32.28 μm to 23.65 μm. The apparent density, electrical conductivity and flexural strength of the SCF/Cu composites increase first and then decrease, the open porosity decreases first and then increases, and the hardness does not change significantly. The comprehensive physical and mechanical properties of the SCF/Cu composites prepared by ball milling for 3 h are good, with apparent density, porosity, electrical conductivity, bending strength and hardness of 7.93 g/cm3, 4.53%, 38.73 MS/m, 332.94 MPa and 46.17 HV, respectively.
Key words: resin-coated short carbon fiber; ball milling dispersion; regulation; microstructure; physical properties; mechanical properties
