江苏11选5走势图

  • <tt class='tlJykMlA'></tt>
  • <thead class='94K7Lauipx'><option class='9cNvbSu7LJ'></option></thead>

    <em class='jepytdnyfeW3'><b class='oR1Ys12nk'><td class='6rzzLTN'></td></b></em>

  • <dl class='Td0EmkF'><b class='qoWhaibfJ9'></b></dl>

  • <span class='lS1G'></span>

    13733919801/13592198132

    冶金★知识

    当前位置:舞阳钢铁 > 冶金★知识 >

    42CrMo优质合金★结构钢板42CrMo4力学性能〓42CrMo化学成

    作者:李成13733919801 发布时间:2020/02/28 点击量:

    江苏11选5走势图  
    42CrMo是一种综合机械性能〓好、淬透性能〓好、应用广泛的中碳合金★结构钢。在机械行业↘中 ,常用于制造齿轮、连杆、高强度螺栓等重要零部件。在生产制造中 ,我们经常遇到欧洲国家的图纸中提到42CrMo4的材料→ ,但是在国标中为42CrMo ,这两个牌号是否通用 ,有何区别 ,各自有何特点。
    42CrMo is a kind of medium carbon alloy structural steel with good comprehensive mechanical properties, good hardenability and wide application. In the mechanical industry, it is often used to manufacture important parts such as gears, connecting rods, high-strength bolts, etc. In the production and manufacturing, we often encounter 42CrMo4 materials mentioned in the drawings of European countries, but 42CrMo in the national standard. Whether these two brands are universal, what are the differences, and what are the characteristics of each.
    针对以上  问题 ,我们详细讨论如下。 
      1.依据标准 
      42CrMo是GB/T 3077合金★结构钢技术条件中的牌号 ,42CrMo4是EN10083 淬火钢№和回火钢中的牌号 ,两者来自于不同的标准。 
      2.化学成分 
      42CrMo 及42CrMo4的化学成分如表1、表2所示: 
      表1 GB3077标准42CrMo的化学成分 
      元素 C Si Mn Cr Mo 
      要求 0.38-0.45 0.17-0.37 0.40-0.70 0.09-1.20 0.15-0.25 
      表2 GB3077标准42CrMo的P、S含量 
      钢类 P S 
      不大于 
      优质钢 0.035 0.035 
      高级优质钢 0.025 0.025 
      特级优质钢 0.025 0.015 
       
      有上  述表可以看出 ,Si、Mn、Mo含量存在差别 ,P、S含量GB3077标准分为三个等级 ,EN10083标准只限定了最高含量。GB3077标准中高级优质钢P、S含量与E10083N标准相当。Si、Mo含量范围GB3077标准要比EN10083标准范围窄;Mn含量GB3077标准要低于EN10083标准。如果只考虑化学成分 ,42CrMo在注意Mn含量的情况下 ,选用高级优质钢可满足EN10083中 42CrMo4的要求。 
    It can be seen from the above table that there are differences in the contents of Si, Mn and Mo. the standard of P and s content gb3077 is divided into three grades, and en10083 only limits the highest content. The content of P and s in gb3077 is equivalent to e10083n. The content range of Si and Mo in gb3077 standard is narrower than that in en10083 standard; the content of Mn in gb3077 standard is lower than that in en10083 standard. If only chemical composition is considered, 42CrMo can meet the requirements of 42CrMo4 in en10083 when high quality steel is selected with attention to Mn content.
      3.淬透性 
      GB标准中淬透性为特殊要求 ,但是未给定淬硬带宽的具体数值 ,供需双方可在订货时协商(在GB5216中有此钢种的淬硬带宽要求 ,可参考)。 
      EN标准中给出了淬硬带宽 ,具体分为H、HL、HH三个等级 ,供订货时参考选用 ,也为设◢计者选用提供了标准资料。 
      4.机械性能〓 
      关于取▓样的位置及方法 ,在GB标准规定 ,按GB/T 2975 要求取▓样 ,即棒材直径d>50mm时 ,以到棒材外径的距离d/4为中心取▓样 ,试棒直径为25mm ,再按标准热处理工▲艺要求进行调质 ,再制成拉伸试样№和冲击试样进行检验ζ。而在EN标准中规定 ,将棒材按推荐热处理工▲艺进行调质 ,然后在棒材上  取▓样 ,棒材直径d>25mm ,取▓样位置为以距离棒材外径12.5mm为中心 ,将试棒制成拉伸试样№和冲击试样进行检验ζ。对于冲击试验ζ标准的试样 ,GB标准采用夏比U型缺口试样 ,而EN标准采用夏比U型缺口试样 ,两种试样的缺口深度一样 ,而缺口底部的半径不同 ,U型为1mm ,V型为0.25mm ,V型缺口应力相对集中 ,当试样受到冲击时 ,就显得更敏感。过去我国主要采用U型缺口试样 ,为了适应一些企业↘的需求 ,后来我国颁布了GB2106金★属夏比(V型缺口)冲击试验ζ方法 ,供特殊需求的钢材使用。在两种标准中 ,都对相应的热处理规范及机械性能〓要求。 
    As for the position and method of sampling, according to the GB standard, sampling shall be conducted according to the requirements of GB / T 2975, i.e. when the diameter of the bar is more than 50 mm, sampling shall be conducted with the distance D / 4 from the outer diameter of the bar as the center, and the diameter of the test bar shall be 25 mm, and then tempering shall be conducted according to the requirements of the standard heat treatment process, and then tensile sample and impact sample shall be made for inspection. According to the en standard, the bar is tempered according to the recommended heat treatment process, and then the sample is taken on the bar. The diameter of the bar is more than 25 mm, and the sampling position is 12.5 mm away from the outer diameter of the bar. The test bar is made into tensile sample and impact sample for inspection. For the specimen of impact test standard, GB standard adopts Charpy u-notch specimen, while en standard adopts Charpy u-notch specimen. The notch depth of the two specimens is the same, but the radius of the notch bottom is different, the u-notch is 1mm, the V-notch is 0.25mm, and the V-notch stress is relatively concentrated. When the specimen is impacted, it is more sensitive. In the past, u-notch specimens were mainly used in China. In order to meet the needs of some enterprises, China issued gb2106 metal Charpy (V-notch) impact test method, which is used for steels with special needs. In both standards, the corresponding heat treatment specifications and mechanical properties are required.
      5.低倍与非金★属夹杂 
      对于低倍组织 ,在GB3077中按钢材的质量等级给出了相应的低倍组织质量要求 ,而在EN标准中未给出低倍组织的相关要求。 
      对于非金★属夹杂 ,在GB3077中未提出要求№和推荐值 ,只要求供需双方协商 ,而在EN10083对非金★属夹杂提出相关要求№和检验ζ方法 ,便于供需双方协商。 

    For macrostructure, the corresponding quality requirements of macrostructure are given in gb3077 according to the quality grade of steel, but the relevant requirements of macrostructure are not given in en standard.
     
    For non-metallic inclusions, there are no requirements and recommended values in gb3077, only consultation between the supplier and the demander is required, while relevant requirements and inspection methods are proposed in en10083 for the convenience of consultation between the supplier and the demander.

      6.晶粒度 
      在GB3077中 ,晶粒度作为特殊要求提出 ,供需双方协商 ,可在合同中注明 ,要求提供不小于5级的细晶粒钢。在EN10083中 ,要求晶粒度细于或等于5级 ,并且给出了相应的检测方法及热处理淬火条件 ,以供选择。 
    In gb3077, the grain size is proposed as a special requirement, which can be indicated in the contract through negotiation between the supplier and the demander. The fine grain steel of no less than grade 5 is required. In en10083, the grain size is required to be smaller than or equal to grade 5, and the corresponding testing method and heat treatment and quenching conditions are given for selection.
      7.交货状态 
      在GB3077中 ,钢材通常以热轧或热锻状态交货 ,如果需方要求热处理(退火、正火或高温回火)状态交货 ,需要在合同中注明。但EN10083中给出5种交货状态供选择 ,分别为不做热处理、热处理以提高切削性能〓、软化退火、淬火并高温回火及其它热处理状态。 
      综上   ,通过对两种标准对于42CrMo钢化学成分、淬透性、机械性能〓、低倍与非金★属夹杂、晶粒度及交货状态的讨论 ,总结如下: 
      7.1EN10083标准规定详细、严格 ,GB3077标准相对简略、宽松; 
      7.2EN10083标准中对于机械性能〓的检测要求 ,直接反应了钢材实际应用时的材料→性能〓 ,便于设◢计者校核计算︻; 
      7.3EN10083标准中明确规定了淬透性的相关要求 ,选用42CrMo4钢做齿轮工▲件时 ,选择此标准订货比较便捷; 
      7.4当企业↘需要批量生产时 ,选择EN10083标准供货较便捷 ,当企业↘单件或小批量生产时 ,选择GB3077标准供货较便捷; 
      7.5 标准的产生与国家的机械制造行业↘发展状况是相辅相成的。在欧洲国家 ,冶金★企业↘大多会配置相应的热处理设◢备 ,以满足机械企业↘的不同订货要求。而在我国 ,机械企业↘的热处理设◢备配置较冶金★企业↘齐全 ,所以我们的大多用户对于钢材的交货状态不做热处理要求 ,而是自己完成。 

    In gb3077, steel is usually delivered in hot rolling or hot forging state. If the demander requires delivery in heat treatment (annealing, normalizing or high temperature tempering), it shall be noted in the contract. However, five delivery states are given in en10083, namely, no heat treatment, heat treatment to improve cutting performance, softening annealing, quenching and high temperature tempering and other heat treatment states.
     
    In conclusion, through the discussion of the chemical composition, hardenability, mechanical properties, low magnification and non-metallic inclusions, grain size and delivery state of 42CrMo steel in two standards, it is summarized as follows:
     
    7.1en10083 standard is detailed and strict, while gb3077 standard is relatively simple and loose;
     
    7.2 the requirements of en10083 for mechanical properties test directly reflect the material properties of steel in practical application, which is convenient for designers to check and calculate;
     
    7.3en10083 standard clearly specifies the requirements of hardenability. When 42CrMo4 steel is selected as gear workpiece, it is convenient to choose this standard for ordering;
     
    7.4 when the enterprise needs mass production, it is more convenient to choose en10083 standard for supply, and gb3077 standard for supply when the enterprise needs single piece or small batch production;
     
    7.5 the emergence of standards and the development of the national machinery manufacturing industry are complementary. In European countries, most metallurgical enterprises will be equipped with corresponding heat treatment equipment to meet the different ordering requirements of machinery enterprises. In China, the heat treatment equipment configuration of mechanical enterprises is more complete than that of metallurgical enterprises, so most of our users do not require heat treatment for the delivery status of steel, but complete it by themselves.

    地址:江苏11选5走势图 电话:13733919801 13592198132 Copyright © 2006-2016 WYGT.CO 江苏11选5走势图版权所有
    技术支持江苏11选5走势图: