【作者】 师晓莉；

【导师】 王伯健；

【作者基本信息】 西安建筑科技大学 ， 材料加工工程， 2005， 硕士

【摘要】 本文通过对比瑞士Graf公司的OK40、OB20金属针布齿条和国内某著名针布生产企业的SWRH72B、SWRH57B金属针布齿条的化学成分、组织和性能,从材质和制备工艺方面探讨了提高金属针布耐磨性和齿条内在质量的可能性。实验结果表明:(1) 化学成分:国外金属针布样品C质量分数较高,其质量分数已达到0.8%。P、S质量分数极低,其质量分数均为0.008%;另外,合金中还加入了W、V、Cr等合金元素,合金元素总质量分数在0.70%～1.16%之间。(2) 显微组织:国外金属针布样品齿条齿尖组织为极细隐针状马氏体+残余奥氏体+粒状碳化物,碳化物分布一级;而国内为较粗隐针状马氏体+残余奥氏体+少量弥散碳化物,碳化物分布一级,但齿条边缘脱碳比较严重。国外齿条基部组织为粒状珠光体,国内齿条基部组织也为粒状珠光体,但碳化物颗粒明显比国外粗大,碳化物的数量也较少。观察还发现,国外齿条比国内的淬硬层深度明显深,OK40的淬硬层百分比值(淬硬层深度/齿总高)为84%,而国产道夫针布AD4523的淬硬层百分比值仅为43%。(3) 显微硬度:国外金属针布样品齿尖硬度普遍超过了HV900,有的甚至超过了HV1000,而国内针布齿尖硬度在HV800左右;国内针布第2点硬度不稳定,有的仅为HV400,而国外均在HV900以上;基部3,4点硬度国内较国外偏低,国外在HV230～HV270之间,而国内在HV145～HV200之间,硬度分布也极不均匀。(4) 国外金属针布齿尖存在镀层。据此提出从改善材质、改进热处理工艺、进行表面处理工艺和设备研制等方面提高金属针布的内在质量的几点建议。 分析了在酸性条件下金属针布表面化学镀镍工艺,通过对温度、pH值等影响因素的分析,找出了最合适的镀液组成及最佳施镀工艺,设计了合理的金属针布表面酸性化学镀镍工艺流程。对国内SWRH72B锡林针布齿条AC4045进行施镀。研究了施镀时间与镀层增重、镀层厚度、镀层组织和性能的关系,并探讨了化学镀镍的机理。实验结果表明:(1) 在本实验条件下,金属针布化学镀镍磷镀层增重随时间的延长而增大,镀层增重与施镀时间满足以下关系:Y=0.0005X+0.0013,相关系数r=0.989128557。短时间内镀速(镀层厚度/施镀时间)稳定。(2) 镀层组织为低磷镀层,镀层同时具有以沉积强更多还原

【Abstract】 The chemical component, microstructure and mechanic properties are analyzed of the local card clothing of SWRH72B, SWRH57B made by a famous manufacturer and OK40, OB20 made by Graf company in Switzerland. Several views are raised on the possibility to improve the abrasion resistance and inside quantity of card clothing on materials and manufacturing process. The results show that: (1) In the aspect of alloying components: The C content of abroad products is higher, already to 0.8%. P, S contents are very low for 0.008%, and alloying elements W, V, Cr are added, which content is 0.7%~1.6%. (2) In the aspect of the microstructure: The abroad tips microstructure is much thin aphanic martensite + retained austenite+ dispersion particle carbide, the carbide distributes even and is the first degree, but the domestic is more rough aphanic martensite + retained austenite + little dispersion carbide, and the decarbonization in the edge is also serious. The abroad has an ideal microstructure of spherical pearlite on the base, but the domestic is more bulky. The particle carbide is obviously bigger and the amount is more than the domestic. The quenching depth of the abroad tips is obviously higher than the domestic. The quenching depth percent is different, and OK 40 is 84%, but the local is only 34%. (3) In the aspect of the microhardness: The abroad tips hardness is higher than the local and to be over HV900 and some is higher than HV1000.The hardness of 2 of the abroad is above HV900, but the local is only HV400 and not stable. The hardness on the base of the abroad is higher than the local, which is between HV145 and HV200 and not even, but the abroad is between HV230 and HV270. (4) A plating coat is found on the abroad tips. So the advices on new material, better heat treatment and surface treatment and its equipment are given.The chemical nickeling process for the card clothing under acid condition is analyzed .The most suitable component of plating solution and the best plating technology is obtained by studying the influencing factors of temperature, pH, etc. Then a reasonable chemical nickeling process on card clothing is designed. Finally thedomestic product of cylinder card clothing wires of AC4045 is plated. The research on the principle and the relation between the time and thickness, structure, property of plating coat is given. Results indicated that: (1) Under this given conditions, the relation between the increment of weight and the time is Y=0.0005X+0.0013, related coefficient r =0.989128557. The speed of plating is stable in a short time. (2) A plating coat of low phosphorus is got. The plating coat has both the main sedimentation enhances (Ni3C phase), and solution strengthening (the P dissolves into the Ni sosoloid solid solution) enhancation mechanisms. After heat treatment, the hardness reaches to HV1000. (3) As is shown in the paper, when the chemical plating time on the card clothing is within the scope of 8~10 min, the thickness of plating coat is already above 6um. The abrasion experiment shows that the surface abrasion resistance of the card clothing is highly increased, which is 2 to 3 times than the common quenching wires. In a word, the surface treatment of chemical nickel-plating on the card clothing wires is viable.In the end, a production line of chemical nickeling plating on the burnishing card clothing is designed by using the results of experiments.更多还原