铜及铜合金中铜量分析方法综述

现行标准ＧＢ５２３１－ＧＢ５２３５－８５中共有８８个合金牌号要求测定铜量，其含铜量从５３％到９９．９７％以上。本文就ＩＳＯ、ＧＢ和主要铜材生产企业分析规程中铜量测定方法，结合本人的实践经验进行综述。     

激光熔覆用钴基合金粉末的研究

对激光熔覆用WFLC－11钴基合金粉末的激光熔覆工艺和熔覆层性能进行了研究，获得了WFLC－11钴基合金粉末激光熔覆层厚度与最小比能量关系曲线和熔覆层的组织、高温硬度等性能数据，为选择和使用WFLC－11钴基合金粉末提供了依据。     

激光焊接超细基胎体金刚石薄壁钻

采用激光焊接超细预合金粉胎体，开发了新的薄壁钻产品，通过对与现有的产品工艺、性能测试以及实际使用分析对比，结果表明：激光焊接与普通钎焊相比结合强度提高2－3倍，克服了胎体脱落问题，胎体耐磨性提高了50％－120％，其中轴向磨损速率提高1．2倍；钻削速度提高30．4％，工矿适应性增加，使用寿命提高25％－108％。     

TiAl基合金粉末爆炸烧结特性常数的测算

本文测算了自蔓延高温合成TiAl基合金粉末的爆炸烧结特性常数值：γ＝1．44，lgβ＝25．25，并为试验证实，这为获取大尺寸TiAl基合金提供了理论依据。     

添加高速钢粉对烧结钢组织与性能的影响

研究了添加高速钢粉对烧结钢组织与性能的影响。实验结果表明，含２０％高速钢的烧结钢综合力学性能最好；添加高速钢粉能导致烧结钢密度减小的冲击韧性降低，当高速钢含量增中时，硬度随之增加，烧结钢中残余奥氏体和马氏体的含量与高速钢的含量呈线性关系。烧结钢中的马氏体显微硬度很高，它主要原高速钢粒子和原铁粒子的连接区域形成。     

粉末冶金压机的应用与进展

简要介绍了当前国内以压制方法生产粉末冶金零件的企业所用压机的基本情况；国内粉末冶金压机生产与开发状况；现代国外知名品牌压机的技术特点与最新发展；分析和总结。     

The magnetic applications choice among ferrite ceramics,metallic strips,or metal powder cores

Iron-based metallic strip materials such as iron, silicon-iron, and amorphous metal are used for low frequency (50–60 Hz. line) power applications. Low-loss Nickel-based alloys as high permeability strip or insulated powder cores are the choices for stable, low-level higher frequency applications. Iron-based powder cores offer low cost as power supply filter chokes. Ceramic ferrites combine highest frequency operation with low cost and reduced component size as transformers and chokes in telecommunication and high frequency power supply applications.     

Three-Dimensional Solution and Experimental Confirmation for the Electric Resistivity Testing of Surface-Breaking Defects in Green-State Powder Metallurgy Compacts

This paper investigates electrostatic voltage distributions around a surface-breaking flaw due to an injected current of known strength. The direct 3-D solution of the voltage behavior over the flawed surface is obtained numerically by the use of a boundary integral formulation. A novel iteration method is applied to solve the resulting electrostatic integral equation for the unknown surface voltage distribution. In addition to investigating the sensitivity of different flaw sizes to the observed surface voltage distribution, important issues such as suitable probe spacing and current flow orientation are studied. For sufficiently small surface-breaking flaws, a simple image source model is developed to evaluate the voltage response of hairline cracks. The model is tested by comparing it with the developed numerical solution. Experiments aimed at establishing the validity of the modeling approach show remarkable agreement with the theoretical model.     

使用矩阵实现LRU的页面置换算法

操作系统的内存管理一直是计算机领域研究的一个重要方向。文中分析了几种常用内存管理中的页面置换算法及其存在的问题,提出了LUR页面置换算法的操作系统内存管理中比较接近理想算法的一种页面置换算法,并阐述了使用矩阵方法实现该页面置换算法的原理。