铸铁件电弧冷焊熔合区白口组织的控制

进行了冷焊条件下控制铸铁件焊补区白口组织的试验．结果表明，采用Ｓｉ－Ｃａ－Ａｌ－Ｂｉ系合金粉层对焊补熔合区进行集中强石墨化孕育处理及焊前在缺陷表面形成Ｎｉ基合金粉末喷涂层，均可消除熔合区白口     

无油沟圆柱滚子轴承滚道及挡边磨加工方法

在介绍圆柱滚子轴承滚道无油沟套圈的磨削加工方法的过程中,重点阐述了在3M1420沟道磨床中采用成形切入磨削方法及砂轮修整时的改进方案。实践证明,采用成形切入磨削的加工方法,能够实现无油沟滚道的加工。     

水轮机主轴密封漏水的故障分析及处理

简述水轮机主轴密封的结构与工作原理,分析主轴密封漏水的原因。通过改造原主轴密封供水管路,提高主轴密封水压力等,解决了主轴密封漏水偏大的问题。改造后的主轴密封运行平稳,漏水量在设计范围之内。     

Ni3Al matrix high temperature self-lubricating composites

A Ni₃Al matrix high temperature self-lubricating composite Ni₃Al-BaF₂-CaF₂-Ag-Cr was fabricated by the powder metallurgy technique, and tribological behavior at a wide temperature range from room temperature to 800 °C was investigated. The results indicated that the composite exhibited low friction coefficients (0.30-0.36) and wear rates (0.65-2.45×10⁻⁴ mm³ N⁻¹ m⁻¹). It was found that the low friction coefficient was attributed to the synergistic effects of Ag, fluorides and chromates formed in the tribo-chemical reaction at high temperatures. The low wear rate of the composite was due to the high strength and the excellent lubricating properties.     

Effect of Ag and Ti3SiC2 on Tribological Properties of TiAl Matrix Self-lubricating Composites at Room and Increased Temperatures

Dry sliding tribological properties of TiAl matrix self-lubricating composites (TMSC) containing Ag, Ti₃SiC₂, Ag and Ti₃SiC₂ were investigated from 25 to 800 °C under ball-on-disk test conditions against Si₃N₄ counterface under the same conditions of 10 N-0.234 m/s. The results indicated that the tribological properties were strongly dependent on the lubricant additives. TMSC with the addition of Ag and Ti₃SiC₂ (TAT) exhibited the lower friction coefficients (0.32–0.43) and less wear rates (1.23–4.13 × 10^?4 mm³ N^?1m^?1) in the wide temperature range of 25–800 °C. The excellent tribological properties of TAT over the wide temperature range were attributed to the synergetic effect of Ag and Ti₃SiC₂ lubricants, silver diffusion forming a rich-silver smooth tribo-film on the frictional surface of TAT at low and moderate temperatures from 25 to 400 °C, while Ti₃SiC₂ oxidation reaction forming rich-oxide tribo-film on the worn surface of TAT at higher temperatures of 600 and 800 °C.     

M22机用丝锥产生裂纹的原因分析与探讨

在M22机用丝锥蒸汽处理后发现有批量的产品存在裂纹,经过分析认为:裂纹产生于机加工的磨槽工序,磨削过程中产生了加工变质层,导致产生了磨削应力。在机加工后,磨削应力转变成残余磨削应力,磨削应力以及残余磨削应力的本质是拉应力,应力在丝锥牙根处集中导致裂纹的产生和扩展。     

快锻液压机泵阀复合控制系统节能性研究

为了从快锻液压机的能量源头出发降低系统的溢流损失和压力损失,提出了一种快锻液压机泵阀复合控制系统,通过相关理论对泵阀复合控制系统的节能机理进行了定性分析,通过实验定量研究了泵阀复合控制系统的能耗。实验结果表明：快锻液压机泵阀复合控制系统的能量利用率达到了31.9%,与电液比例阀控系统相比提高了近5倍,同时泵阀复合控制系统的输入功率仅为电液比例控制系统的18.4%。研究结果对提高快锻液压机的能量利用率并降低系统能耗具有重要意义。     

W9Mo3Cr4V轧制Φ2.5mm直钻热处理萘状断口的原因探讨

在淬火过程中发现Ф2.5mm直钻的晶粒度出现异常,有萘状断口,通过实验以及分析认为,钻头在加工过程中满足了萘状断口长大的条件:形变织构、原始晶粒细小、碳化物的强钉扎作用,加热温度高、加热时间长,从而造成晶粒的异常长大。萘状断口晶粒对钻头的韧性构成严重危害,通过改进加热方式和热处理工艺,可以消除萘状断口。     

基于MSP430的HART协议流量计设计

叙述了基于MSP430单片机的HART协议流量计设计,介绍了该流量计的结构及其软硬件设计。详细介绍了采用HT20C15及AD421构成的HART协议通信线路设计。     

关于油田注汽锅炉水循环方式的简析

基于油田稠油开采回用水的给水品质、蒸汽干度等多方面要求,分析比较了锅炉的几种不同水循环方式的优缺点,并提出注汽锅炉采用分段蒸发的自然循环锅炉水循环方式是最合适的。