本文關(guān)鍵詞：人造金剛石表面化學(xué)鍍Ni-Mo-P三元合金實(shí)驗(yàn)研究　出處：《遼寧科技大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 化學(xué)鍍 鍍層 人造金剛石

【摘要】：人造金剛石具有超高硬度、高導(dǎo)熱率、低摩擦系數(shù)等諸多優(yōu)良性質(zhì),它廣泛應(yīng)用于工業(yè)生產(chǎn)中。但利用人造金剛石制造的工具在使用時存在一些問題。由于金剛石與胎體之間有較高的界面能,兩者不能很好地浸潤,使得工具的使用壽命大打折扣。此外,人造金剛石的耐熱性不高,高溫下易氧化失重或石墨化。目前主要解決方法是利用化學(xué)鍍技術(shù)使人造金剛石表面金屬化,使鍍覆后的金剛石與胎體能夠牢固結(jié)合,同時提高了人造金剛石的抗氧化性、熱穩(wěn)定性、耐磨性等特性。常用的金屬鍍層包括Ni-P、Ni-B等二元金屬鍍層,隨著科技的快速進(jìn)步,傳統(tǒng)的二元金屬鍍層已經(jīng)不能滿足工業(yè)發(fā)展的需要。本文在化學(xué)鍍Ni-P的基礎(chǔ)上,進(jìn)行工藝優(yōu)化改進(jìn),引入了在高溫下強(qiáng)度高、硬度高、膨脹系數(shù)低、耐蝕性好的金屬鉬(Mo),在金剛石表面形成高硬度,孔隙少,高耐蝕性等特點(diǎn)的Ni-Mo-P合金鍍層。對人造金剛石粉體首先進(jìn)行除油、粗化、敏化、活化、解膠等預(yù)處理,并選擇合適的主鹽和添加劑配制鍍液,然后對人造金剛石粉體進(jìn)行化學(xué)鍍,最終獲得表面鍍覆有Ni-Mo-P合金鍍層的粉體。鍍層致密均勻,粉體包覆嚴(yán)實(shí),具有金屬光澤。其次,采用正交實(shí)驗(yàn)的方法,結(jié)合鍍層鍍覆效果及沉積速度,確定了人造金剛石粉體化學(xué)鍍Ni-Mo-P合金鍍層的最佳施鍍方案:鉬酸鈉濃度為0.8/L,硫酸鎳濃度為25g/L,次亞磷酸鈉濃度為29g/L,十二烷基硫酸鈉濃度為0.1g/L,氟化鈉濃度為1.5g/L,pH為4.5,溫度為86℃。絡(luò)合劑用量為28 g/L,鍍覆時間為1.5h。利用掃描電子顯微鏡(SEM)、能譜儀(EDS)的檢測方法,分析鍍層的表面形貌、鍍覆效果、鍍層成分;用激光粒度儀對鍍覆后的人造金剛石粉體的粒度進(jìn)行檢測,粒徑分布集中,粉體各項(xiàng)性能較好;進(jìn)行了高溫煅燒實(shí)驗(yàn),實(shí)驗(yàn)結(jié)果顯示表面鍍層能夠提高金剛石的耐熱性。通過理論研究、施鍍工藝優(yōu)化及測試分析表明:人造金剛石表面鍍覆Ni-Mo-P合金鍍層理論和工藝可行,鍍層性能良好,降低了應(yīng)用成本,提高了人造金剛石的使用壽命。得到的施鍍原理與施鍍工藝豐富了新型多元化合金鍍層的發(fā)展,為人造金剛石表面鍍覆Ni-Mo-P合金鍍層的工業(yè)化應(yīng)用提供了理論依據(jù)和技術(shù)支持。
[Abstract]:Synthetic diamond has many excellent properties, such as high hardness, high thermal conductivity, low friction coefficient and so on. It is widely used in industrial production, but there are some problems in the use of synthetic diamond tools. Because of the high interfacial energy between diamond and matrix, they can not be well infiltrated. Besides, the heat resistance of synthetic diamond is not high, and it is easy to be oxidized or graphitized at high temperature. At present, the main solution is to use electroless plating technology to metallize the surface of synthetic diamond. The coated diamond can be firmly bonded with the matrix, and the oxidation resistance, thermal stability and wear resistance of the synthetic diamond are improved. The commonly used metal coatings include Ni-P. With the rapid progress of science and technology, the traditional binary metal coating, such as Ni-B, can no longer meet the needs of industrial development. Based on the electroless plating of Ni-P, the process optimization is carried out in this paper. The high hardness, high hardness, low coefficient of expansion and good corrosion resistance of molybdenum are introduced at high temperature to form high hardness and less porosity on diamond surface. Ni-Mo-P alloy coating with high corrosion resistance. The synthetic diamond powder was first treated with deoiling, coarsening, sensitization, activation and gel decomposition, and the appropriate main salt and additives were selected to prepare the bath. Then the synthetic diamond powder is electroless, and the powder coated with Ni-Mo-P alloy coating is obtained. The coating is dense and uniform, and the powder has metallic luster. By means of orthogonal experiment, combined with coating effect and deposition speed, the optimum plating scheme of Ni-Mo-P alloy coating for synthetic diamond powder electroless plating was determined: the concentration of sodium molybdate was 0.8 / L. Nickel sulfate concentration is 25 g / L, sodium hypophosphite concentration is 29 g / L, sodium 12 alkyl sulfate concentration is 0.1 g / L, sodium fluoride concentration is 1.5 g / L, pH is 4.5 g / L. The temperature was 86 鈩，

本文編號：1410126