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[summary]To develop and use the power silicon recfier and thyris- tor is an important problem,particularly in the sense of energy—sa- ving;and zherefore,the manufacture of power semi-conductor device with high voltage,large current and quick switching speed is the main trend of the development. Of these requirements,The high voltage is the most difficultone a mong the three.In the world market,the power somiconductor device which exeeds 4000 volts is still uncommon. we have succeeded in making the p—n junction... [summary]To develop and use the power silicon recfier and thyris- tor is an important problem,particularly in the sense of energy—sa- ving;and zherefore,the manufacture of power semi-conductor device with high voltage,large current and quick switching speed is the main trend of the development. Of these requirements,The high voltage is the most difficultone a mong the three.In the world market,the power somiconductor device which exeeds 4000 volts is still uncommon. we have succeeded in making the p—n junction with 3000~4000 volts in our laboratory,and on The bases of our experiment,we pay atten- tion to the following technical probloms: (1)The deformation of the silicon wafer,by a long time diffusion when heated at a high temperature,must be avoided. (2)The p—n junctions must bekept in a state of flat energy band between inside and surface of silicon. (3)In the process of alloying,any impurities must be eliminated. 从节省能源的意义出发,大功率硅整流元件和晶闸管的制造及应用在国民经济中占有不可低估的作用。元件的高压化、大电流化、快的开关速度化将成为今后大功率半导体器件的明确发展方向。在高耐压化、大电流化、快的开关速度化特性中,其中高耐压化受工艺技术难度的影响比较大。目前,就国际水平范围内,超4000伏耐压也还很不普遍。为了突破大功率半导体元件高耐压的问题,我们的实验室试做了3000—4000伏耐压的 p-n 结,并以此为基础,对有关工艺技术问题做些探讨。 In this paper the author mainly introduces the present situation and future development of high-voltage HRC fuse.It elucidates the construction of fuse element and its materials,the location of alloy of eutectic alloying effect (M-effect),kind of sand filled and choice of cartridge material.Moreover,the main parameters and construction of sonic typical high-voltage HRC fuses of foreign made are introduced.There has been a full capability of manufacturing the high-voltage HRC fuse in China. 本文主要介绍限流式高压熔断器的现状和今后发展的方向。阐述当前这种熔断器熔体的结构和材料,冶金效应合金的布置,填料的种类以及外壳的选用。最后介绍几种典型的国外限流式高压熔断器的参数和结构,并指出我国目前己完全具备生产这种熔断器的能力。 We review recent NBS studies on austenitic-slainless-steel elastic constants at low temperatures.By measuring velocities of longitudinal and shear waves,we determined accurately the usual engineering elastic constants.Young modulus,shear modulus,bulk modulus ( reciprocal compressibility) ,and Poisson ratio.We consider effects of alloying,temperature,magnetic field,and sample-to-sample variability,we also consider the monocrystal-polycrystal relationship.Due to magnetic transitions,most of these alloys... We review recent NBS studies on austenitic-slainless-steel elastic constants at low temperatures.By measuring velocities of longitudinal and shear waves,we determined accurately the usual engineering elastic constants.Young modulus,shear modulus,bulk modulus ( reciprocal compressibility) ,and Poisson ratio.We consider effects of alloying,temperature,magnetic field,and sample-to-sample variability,we also consider the monocrystal-polycrystal relationship.Due to magnetic transitions,most of these alloys exhibit low-temperature elastic-constant anomalies.The transitions occus over a temperature range,but show reversible behavior and are probably second-order.A magnetic-susceptibility cusp occurs near the shear-modulus transition temperature.Due perhaps to local moments above Tc,the bulk-modulus maximun occurs at a higher temperature.Increased nickel content lowers the transition temperature while increased manganese raises it. 本文报道了美国国家标准局近来有关奥氏体不锈钢在低温下的弹性常数的研究。通过测量纵向波和剪切波的速度,精确测定了普通的工程弹性常数,即杨氏模量、剪切模量、体积模量(可逆压缩系数)和泊松比。研究了合金化。温度、磁场的影响,以及逐个试样的离散性。另外还研究了单晶体和多晶体的关系。由于磁性转变,大部分合金的低温弹性常数呈异常现象。该转变发生在某一个温度范围内,但显示了可逆性,这可能是二级相变。磁化率的峰出现在剪切模量的转变温度附近。大概是由于Tc以上温度的局部力矩作用,体积模量的最大值出现在较高温度。增加镍量,可使转变温度降低,然而,增加含锰量,却使转变温度提高。
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