低合金钢机械性能

低合金钢机械性能低合金钢是指在钢中加入少量合金元素（符合表5-1）由于合金元素的强化作用，低合金结构钢的屈服点比普通碳素钢高25-150%加之大多低碳，而具有良好的塑性韧性和焊接性能，有的还具有耐腐蚀、耐低温等特性，因此，低合金钢是一类很有发展前途的钢，在钢的生产中比例越来越大。低合金钢按质量和用途分为普通质量低合金钢、优质低合金钢、特殊质量低合金钢。16、一般用途低合金钢一般用途低合金结构钢包括：普通质量和优质低合金结构钢、普通质量低合金钢是指生产过程中不规定特别控制质量要求的供一般用途、 优质、在生产过程中需要特别控制质量（例降低硫、磷含量、控制晶粒度，改善表面质量等）一般用途低合金钢结构钢牌号由代表屈服点的汉语拼音字母（ Q）、屈服点数值、质量等级符号（A、B、C、DE）三个部分按照顺序排列，根据GB/T1591-94低合金高强度结构钢牌号，化学成分及性能见表5-16和表表5-16、低合金高强度结构钢牌号、化学成分牌号质化学 成 分：%量等级C<MnSiP<S<VNbTiAl>CrNiA0.10.80-0.0.50.040.040.02-0.0.015-0.0.02-0.Q2961555515060[205B0.10.80-0.0.50.040.040.02-0.0.015-0.0.02-0.615500L15060」L20A0.21.00-1.0.50.040.040.02-0.0.015-0.0.02-0.060555115060」20B0.21.00-1.0.50.040.040.02-0.0.015-0.0.02-0.Q345060500J15」060L20C0.21.00-1.0.50.030.030.02-0.0.015-0.0.02-0.0.0106055515060I205ID0.11.00-1.0.50.030.030.02-0.0.015-0.0.02-0.0.0186050015060[205E0.11.00-1.0.50.020.020.02-0.0.015-0.0.02-0.0.01

86055515060205A0.21.00-1.0.50.040.040.02-0.0.015-0."!0.02-0.0.30.7060555200602000B0.21.00-1.10.50.040.040.02-0.0.015-0.0.02-0.0.30.7060500200602000Q39C0.21.00-1.0.50.030.030.02-0.0.015-0.10.02-0.0.010.30.700605552006020500D0.21.00-1.0.50.030.030.02-0.0.015-0.10.02-0.0.010.30.70605002006020500E0.21.00-1.0.50.020.020.02-0.0.015-0.0.02-0.0.010.30.70605552006020500A0.21.00-1.0.50.040.040.02-0.0.015-0.10.02-0.0.40.7070555200602000B0.21.00-1.0.50.040.040.02-0.0.015-0.0.02-0.0.40.7070500200602000Q42C0.21.00-1.0.50.030.030.02-0.0.015-0.0.02-0.0.010.40.700705552006020500D0.21.00-1.0.50.030.030.02-0.0.015-0.0.02-0.0.010.40.70705002006020500E0.21.00-1.0.50.020.020.02-0.0.015-0.0.02-0.0.010.40.707055520060|20500A0.21.00-1.0.50.030.030.02-0.0.015-0.0.02-0.0.010.70.7070555J20060120500Q46B0.21.00-1.0.50.030.030.02-0.0.015-0.0.02-0.0.010.70.7007050020060[20500C0.21.00-1.0.50.020.020.02-0.0.015-0.0.02-0.0.010.70.70705552006020500J屈服点6s,MPa质量等级厚度（直径，边长）,mm冲击功，AKV（纵向）,J180。弯曲试验屈服点6s,MPa质量等级厚度（直径，边长）,mm冲击功，AKV（纵向）,J180。弯曲试验+2000-20-40d=弯心直径；°CC°C°C&=试样厚度（直径）不小于钢材厚度（直径），抗拉强度6bMPa伸长率S%<>16-3165>35-50>50-100

mm不小于16>16-100Q295AB295295275275255255235235390-570390-570232334d=2ad=3aQ345ABCDE345345345345345325325325325325295295295295295275275275275275470-630470-630470-630470-630470-6302121222222343434d=2ad=3ad=2ad=3ad=2ad=3a27d=2ad=3ad=2ad=3aQ390ABCDE370370370370370370370370370370350350350350350330330330330330490-650490-650490-650490-650490-650191920202034343427d=2ad=3ad=2ad=3ad=2ad=3ad=2ad=3ad=2ad=3aQ420ABC420420400400400380380380360360360520-680520-68018183434d=2ad=3ad=2ad=3ad=2ad=3a

DE420420420400400380380360360520-680520-680520-6801919193427d=2ad=3ad=2ad=3aC460440420400550-720173434d=2ad=3aQ460460550-7201727d=2ad=3aD440420400E440420400d=2d=3a46550-721a007在旧标准中低合金结构钢的牌号用两位阿拉伯数字和合金元素符号及数字表示，数字表示平均含碳量（以万分之几计）平均合金含量小于 1.5%时，钢号中仅标明元素符号，不标明含量；平均合金含量为 1.5-2.49%、2.5-3.49%时，相应写成品2、3……其牌号、化学成分、性能见表 5-18和表5-19。表5-18、一般用途低合金结构钢牌号、化学成分（根据 GB1591-881）| 化学成分，%牌号REs]匚PCMSiVTiNbCuN加入曰不大于量0.80-0.20-0.04-0.09MnVf——————————040.045:0.121.200.550.12509MnNJ<0.80-0.20-0.015-0.r\Ab0.121.200.550.050045U.U451.40-0.20-0.09Mn————————————040.0450.121.800.5550.09-1.10-0.20-0.12Mn————————————040.0450.161.500.55518Nb0.14-0.40-0.17-————0.020-——————0.0.045

0.220.800.370.05004509MnC:w1.00-0.20-w0.20-0.0.05-uPTi0.121.500.550.030.400450.1210MnS；w1.25-0.80-0.15-0.r\AiCu0.121.601.100.30045U.U45w1.00-0.20-0.04-0.12MnV[—————040.0450.151.400.550.12514MnN0.12-0.80-0.20-0.015-0.b0.181.200.550.050045U.U450.12-1.20-0.20-0.16Mn————————————040.0450.201.600.55516MnF0.12-1.20-0.20-0.02-0.r\AE0.201.600.550.20045U.U4510MnF>w0.80-0.20-0.015-0.02-0.0.06-NbRE0.141.200.550.0500.200450.120.12-1.20-0.20-0.04-0.15MnV——————————040.0450.181.600.550.12515MnT0.12-1.20-0.20-0.12-0.r\Ai0.181.600.550.20045U.U4516MnV0.12-1.00-0.20-0.015-0.r\Ab0.201.400.550.05004U.U45514MnVfw1.30-0.20-0.04-0.09-0.02-0.r\r\AcTiRE0.181.600.550.100.160.200450.04515MnV0.12-1.30-0.20-0.10-0.010-0.————040.045N0.201.700.550.200.0205表5-19、一般用途低合金结构钢机械性能（根据GB1591-88）

牌号钢材厚度或直径mm抗拉强度26sN/mm屈服点6bN/mrn伸长率SS%180C弯曲试验d=弯心直径a=试样厚度冲击试验温度。CV型冲击功（纵向），J不小于不小于09MnV<16430-58029523d=2a2027>16-25275d=3a09MnNb<16410-56029524d=2a2027>16-25390-54027523d=3a09Mn2<16440-59029522d=2a2027>16-30420-57027522d=3a>30-100方、圆钢410-56025521d=3a12Mn<16440-59029522d=2a2027>16-25430-58027521d=3a>25-36400-55025521d=3a>36-50390-54023521d=3a50-100方、圆钢390-54023520d=3a18Nb<16470-62034520d=2a2027>16-25450-60032519d=3a09MnCuPT<16490-64034522d=2a2027>16-25490-64033521d=3a10MnSiCu4-10490-64034522d=2a2027>10-20470-62033522d=2a>20-32470-62032522d=3a12MnV<16490-64034522d=2a2027>16-2533521d=3a14MnNb<16490-64035521d=2a2027>16-25470-62033520d=3a16Mn<16510-66034522d=2a2027>16-25490-64032521d=3a>25-36470-62031521d=3a<36-50470-62029521d=3a

>50-100方、圆钢470-62027520d=3a16MnRE<16510-66034522d=2a2027>16-25490-64032521d=3a10MnPNbRE<10510-66039020d=2a202715MnV<4550-70041019d=2a2027>4-16530-68039018d=3a>16-25510-66037519d=3a>25-36490-64035518d=3a>36-50490-64033518d=3a15MnTi<25530-68039020d=3a2027>25-40510-66037520d=3a16MnNb<16530-68039020d=2a2027>16-20510-66037519d=3a14MnVTiRF<12■550-70044019d=2a20271H-IVI11V11rxl_>12-20530-68041019d=3a15MnV<10590-74044019d=2a2028>10-25570-72042019d=3a>25-38550-70041018d=3a>38-50530-68039018d=3a新旧低合金结构钢标准牌号对照见表 5-20表5-20、新旧低合金结构钢标准牌号对照（参考件）GB1591-88Q29509MnV09MnNb09Mn212MnQ34512MnV14MnNb16Mn16MnRE18NbQ39015MnV15MnT、GB1591-88Q29509MnV09MnNb09Mn212MnQ34512MnV14MnNb16Mn16MnRE18NbQ39015MnV15MnT、16MnNbQ42015MnVN14MnVTiREQ420Q460一般用途低合金