《毕业论文（设计）：大理石对J422焊条工艺性影响研究》由会员分享，可在线阅读，更多相关《毕业论文（设计）：大理石对J422焊条工艺性影响研究（39页珍藏版）》请在金锄头文库上搜索。
1、机机电电工程学院工程学院毕毕 业业 论论 文文论文题目论文题目: : 大理石对大理石对 J422J422 焊条工艺性影响研究焊条工艺性影响研究 摘摘 要要本次设计主要研究大理石对于 J422 焊条的工艺性影响，需要设计试验改变J422 焊条中大理石含量，观察焊条药皮中大理石含量不同对于 J422 焊条的工艺性能的影响，最后得到大理石的最优含量。本次试验共设置 20 组试样，前 3 个试样用来确定药皮质量系数。先根据标准配方配制药粉并搓制 3 根焊条，使它们的药皮质量系数分别为 20%、50%和 80%。在45 钢试样上单面堆焊，记录焊接现象并对试样进行硬度测试，分析焊接接头的组织，选择出最佳药
2、皮质量系数。然后按照确定的药皮质量系数，将标准配方中大理石的含量分别改变为0、3%、6%、9%、12%、15%、18%、21%、24%、27%、30%、33%、36%、39%、42%、45%、48%，药皮中其它的成分等比例增加或减少，搓制 17 根焊条。然后使用自制焊条在45 钢表面单层堆焊，制作 17 个试样，随后对试样进行工艺性能和力学性能的测试，观察焊接接头的显微组织，最后得出结论。试验结果表明：当药皮质量系数为50%，焊条的引弧性、稳弧性最好，焊接飞溅小，脱渣性好，利于施焊者施焊，焊缝成形也很美观。此时焊接接头的焊缝区和热影响区硬度值最大。随着焊条药皮中大理石含量的增加，焊条的引弧性、
3、稳弧性、脱渣性及焊缝成形都逐渐变好，但是焊接飞溅，电弧吹力及套筒却很大。当药皮中大理石含量为18%时，焊条的引弧性和稳弧性较好，电弧吹力适中，渣覆盖率大，脱渣性好，飞溅也小，焊缝成形美观，无气孔裂纹产生，工艺性能最佳。当药皮质量系数为50%时，焊缝区和热影响区的硬度值达到最大，此时45钢焊接接头具有最优的力学性能。随着焊条药皮中大理石含量的增加，45钢焊接接头的焊缝区的硬度值逐渐增大，当大理石的含量超过18%时，焊缝区硬度开始下降，而热影响区硬度值先有所下降，然后回升。当药皮中大理石含量为18%时，焊缝区的硬度值达到最大，热影响区硬度值较大，此时45钢焊接接头具有最优的力学性能。45钢焊接接头
4、的焊缝区和热影响区都分布着贝氏体、珠光体、高碳马氏体组织。但是热影响区中珠光体和粗大的马氏体组织比焊缝区多。当药皮质量系数为50%时，熔合线两侧组织均匀细密，热影响区存在较多的珠光体和贝氏体组织，高碳马氏体I较少。在大理石含量为18%时，焊缝区和热影响区珠光体和铁素体分布均匀，出现较多机械性能好的索氏体，高碳马氏体含量相对减少，显微组织分布最均匀。综上所述，此次试验焊条最佳的药皮质量系数为 50%。在最佳药皮质量系数确定的情况下，当焊条药皮中大理石含量为 18%时，45 钢焊接接头组织最均匀，具有最佳的力学性能和工艺性能。关键词：关键词：J422 焊条、大理石、工艺性能、组织、力学性能IITi
5、tle：The influence of the marble on the processing property of J422 welding rodAbstractThe effect of the marble for the process of J422 electrode was mainly studied in this paper.We could observe how welding performance of 45 steel changed when we changed the content of marble in coating of electrode
6、. Finally we would get optimal levels of marble in the J422 electrode coating.We made three electrodes whose coating quality factor was 20%, 50%, 80%, respectively. Next we should test weldability of them and choose the best one. Its coating quality factor would be applied to the rest of the 17 elec
7、trodes.And the content of marble in coating of these electrodes were 0,3%, 6%, 9%, 12%, 15%, 18%, 21%, 24%, 27%, 30%, 33%, 36%, 39%, 42%, 45%, 48%,respectively. Then we should test weldability of them. Finally we choosed the best one and came to the conclusion.Experimental results showed that the we
8、lding arc and arc stability of electrodes was the best, when the coated quality coefficient is 50%.There was just a little splash.It also has great deslagging, and was applied to weld very well,and appearance of weld joint was beautiful while the hardness value of weld joint is maximum.With the incr
9、ease of the content of marble in the covering of the welding rod, arc stability, slag detachability and weld shaping were gradually getting better, but the welding spatter, arc blow force and the sleeve was bigger.When the marble content in the coating was 18% , resistance and arc stability was bett
10、er while arc blow force was moderate.Slag coverage and deslagging was great and splash was smaller .Weld forming was beautiful.There was also no stomatal and crack in the welded joint.The electrode had the best process performance.When the coated quality coefficient was 50%, hardness value of weld z
11、one and heat affected zone was maximum,while welded joint of 45 # steel had the best mechanical properties.With the increase of the content of marble in the electrode covering , hardness value of 45 steel increased first.when the content of marble was more than 18%,it was gradually on the decline, w
12、hile hardness value of the heat affected zone decreased first, and then picked up.When coated marble content was 18%, hardness value of the weld area was maximum, so was heat affected zone.We thought the welding joint of 45 steel had the best mechanical properties now.Welding joint of the weld zone
13、and heat affected zone had the bainite, pearlite, high carbon martensite.Pearlite and martensite was more in the heat affected zone than the weld area .When coated quality coefficient was 50%, organization on both sides of fusion IIIline was similar but the fusion zone existed more pearlite and bain
14、ite, less high carbon martensite.When marble content was 18%, pearlite and ferrite of the weld zone and heat affected zone was uniform distribution.There was a lot of good sorbite which had better mechanical properties ,less carbon martensite.To sum up, the best coated quality coefficient of the tes
15、t electrode was 50%.And the best content of marble in the electrode covering was 18%.At the time 45 steel welding joint organization was uniform, which had the best mechanical properties and process performance.Keywords: J422 electrode, marble, process performance, organization and mechanical propertiesIV目 录 摘 要.I Abstract.III 1 绪论.1 1.1 引言.1 1.2 国内外焊接材料的研究现状和发展趋势.1 1.3 本文的研究的目的与内容.3 2 试验方法及过程.
