采用等离子填丝焊工艺对轨道车辆用2 mm厚的X2Cr Ni N18-7不锈钢薄板进行对接焊接试验,通过正交试验对焊接电流、焊接速度、送丝速度和离子气流量参数进行了优化,并对最佳工艺参数下的焊接接头质量进行了焊接工艺评定。结果表明:使用Pla...采用等离子填丝焊工艺对轨道车辆用2 mm厚的X2Cr Ni N18-7不锈钢薄板进行对接焊接试验,通过正交试验对焊接电流、焊接速度、送丝速度和离子气流量参数进行了优化,并对最佳工艺参数下的焊接接头质量进行了焊接工艺评定。结果表明:使用Plasmatron等离子焊机成功实现了X2Cr Ni N18-7不锈钢薄板等离子填丝对接焊,优化的焊接工艺参数为焊接电流160 A,焊接速度0.25 m/min,送丝速度3.0 m/min,离子气流量5 L/min;焊缝成形良好,背面全焊透,经X射线探伤无未焊透、未熔合和裂纹等缺陷;焊接接头的综合力学性能良好,焊接接头的抗拉强度平均值为636.57 MPa,焊接接头强度系数为92.28%;180°横向正弯试验结果显示,试样正反两面均无裂纹;当疲劳测试加载循环次数为1.0×107次时,焊接接头的疲劳极限为270 MPa。展开更多
Two kinds of Nd 1+ x Ba 2- x Cu 3O 7- δ , the sintered samples and zone melted samples, were treated in pure Ar at 950 ℃. The substitution of Nd ions for Ba ions in the Nd 1+ x Ba 2- ...Two kinds of Nd 1+ x Ba 2- x Cu 3O 7- δ , the sintered samples and zone melted samples, were treated in pure Ar at 950 ℃. The substitution of Nd ions for Ba ions in the Nd 1+ x Ba 2- x Cu 3O 7- δ before and after the heat treatment was investigated by XRD. In order to know the effects of heat treatment, the T c and J c of samples with and without the heat treatment in Ar were comparatively studied. The results show that the substitution of Nd for Ba decreases, whereas T c and J c increase after the treatment. The Nd 1+ x Ba 2- x Cu 3O 7- δ samples were oxygenated in pure oxygen at 300 ℃ . Based on the XRD spectra it was found that the samples with x <0.4 can transform from tetragonal phase into orthorhombic phase after the oxygenation, whereas in the sample with x >0.4 no phase transition occurs even after a long time oxygenation.展开更多
文摘Two kinds of Nd 1+ x Ba 2- x Cu 3O 7- δ , the sintered samples and zone melted samples, were treated in pure Ar at 950 ℃. The substitution of Nd ions for Ba ions in the Nd 1+ x Ba 2- x Cu 3O 7- δ before and after the heat treatment was investigated by XRD. In order to know the effects of heat treatment, the T c and J c of samples with and without the heat treatment in Ar were comparatively studied. The results show that the substitution of Nd for Ba decreases, whereas T c and J c increase after the treatment. The Nd 1+ x Ba 2- x Cu 3O 7- δ samples were oxygenated in pure oxygen at 300 ℃ . Based on the XRD spectra it was found that the samples with x <0.4 can transform from tetragonal phase into orthorhombic phase after the oxygenation, whereas in the sample with x >0.4 no phase transition occurs even after a long time oxygenation.
基金supported by the grants from the National Natural Science Foundation of China(No.3086008631060139and81171184)+5 种基金the Technology Pedestal and Society Development Project of Jiangxi ProvinceChina(No.2010BSA09500)the Young Scholars Science Foundation of Jiangxi ProvinceChina(No.20122BAB215005)the Youth Science Foundation of the Education Department of Jiangxi ProvinceChina(No.GJJ12149)
