【摘要】：復(fù)合化學(xué)鍍是一種新興的表面處理技術(shù),將它與熱處理、激光處理等技術(shù)相結(jié)合,形成性能優(yōu)異的耐磨性鍍層已成為人們研究的焦點(diǎn)。本論文采用中性鍍液經(jīng)預(yù)鍍+復(fù)合鍍?cè)?5鋼基體表面制備出孔隙率小、鍍層結(jié)合力良好、厚度為20μm左右、含磷量為5.99%的中低磷非晶Ni-P-WC復(fù)合鍍層;研究鍍液中WC的添加量對(duì)鍍速、鍍層形貌及硬度等性能的影響,確定復(fù)合鍍的最佳工藝參數(shù);采用光學(xué)顯微鏡、原子力顯微鏡、掃描電鏡、能譜儀和X射線衍射等手段對(duì)鍍層表面形貌、成分及相進(jìn)行分析。結(jié)果表明,隨著鍍液中WC含量增大,沉積速度逐漸下降,鍍層表面逐漸變暗變黑,其外觀質(zhì)量變差;鍍層起伏由0~2.1μm增加到0~3.7μm,粗糙度增大;鍍層硬度隨著鍍液中WC含量的增多出現(xiàn)先上升后下降的趨勢(shì),當(dāng)WC含量為3g/l時(shí),鍍層硬度達(dá)到最大。對(duì)復(fù)合鍍層進(jìn)行200℃、300℃、400℃、500℃熱處理,發(fā)現(xiàn),鍍層由非晶態(tài)向晶態(tài)轉(zhuǎn)變,并脫溶析出金屬間化合物Ni3P,WC晶粒并未發(fā)生變化,鍍層硬度提高,且在400℃熱處理后硬度達(dá)到最高。對(duì)鍍層采用兩種激光器進(jìn)行處理,發(fā)現(xiàn),鍍層分別在450V~750V電壓下經(jīng)納秒激光器處理,其鍍層形貌隨著電壓增大逐漸呈現(xiàn)出熔融的狀態(tài),但整體依然保持胞狀形態(tài);鍍層硬度隨著激光處理電壓增大出現(xiàn)先升高后降低的現(xiàn)象,并在電壓為550V時(shí)鍍層硬度達(dá)到最高,XRD顯示鍍層依然保持非晶態(tài);經(jīng)光纖激光器處理后的鍍層表面形貌明顯改變,鍍層表面出現(xiàn)顯微微裂紋,且呈現(xiàn)出一種熔融狀態(tài),硬度下降明顯,與純鎳相硬度相當(dāng),XRD表明鍍層有晶態(tài)Ni析出。摩擦磨損實(shí)驗(yàn)結(jié)果發(fā)現(xiàn),經(jīng)納秒激光器激光熔覆后的鍍層摩擦系數(shù)最小,耐磨性最好。對(duì)鎳磷微粒復(fù)合鍍的生長機(jī)制進(jìn)行探討,認(rèn)為在其在含有WC的地方優(yōu)先生長,鎳磷胞互相堆疊,逐層生長。
[Abstract]:Composite electroless plating is a new technology of surface treatment. Combining it with heat treatment, laser treatment and other technologies, it has become the focus of research on the formation of excellent wear-resistant coatings. In this paper, low and medium phosphorus amorphous Ni-P-WC composite coatings with low porosity, good adhesion, thickness of about 20 渭 m and phosphorus content of 5.99% were prepared on the surface of 45 steel substrate by pre-plating composite plating with neutral plating bath. The optimum technological parameters of composite plating were determined by the influence of the morphology and hardness of the coating, and the surface morphology, composition and phase of the coating were analyzed by means of optical microscope, atomic force microscope, scanning electron microscope, energy spectrometer and X-ray diffraction. The results show that with the increase of WC content in the bath, the deposition rate decreases, the coating surface darkens and the appearance quality becomes worse, the undulation of the coating increases from 0 ~ 2.1 渭 m to 0 ~ 3. 7 渭 m, and the roughness increases. With the increase of WC content in the bath, the hardness of the coating increased first and then decreased. When the WC content was 3g/l, the hardness of the coating reached the maximum. The composite coating was heat-treated at 200 鈩，

本文編號(hào)：2141139