Influence of Longitudinal Oscillation on Tensile Properties of Medium Carbon Steel Welds of Different Thickness
Influence of Longitudinal Oscillation on Tensile Properties of Medium Carbon Steel Welds of Different Thickness
复制标题
纵向振动对不同厚度中碳钢焊缝拉伸性能的影响
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
S. Tewari
中科院分区：
文献类型：
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作者：
S. Tewari
研究了试样厚度对中碳钢纵向振动焊缝拉伸性能的影响。在不同频率和幅值的纵向振动条件下对中碳钢进行了焊接试验。振荡频率和振幅分别在0 ~ 400 Hz和0 ~ 40μm范围内变化。从静态和振荡焊接工件的拉伸试验和显微组织检查标本。测试了8 mm、10 mm和12 mm厚的试样，并测定了屈服强度、极限拉伸强度、伸长率、断裂强度、冲击强度和硬度。对试样进行金相检查。与固定焊接试样相比，振荡（纵向）制备的焊缝的屈服强度、极限拉伸强度、断裂强度显著提高，但伸长率百分比（+5.5%）降低。拉伸性能的最大增加（屈服强度-21%，U.T.S.在400 Hz-5 μm振动条件下，焊缝的断裂强度增加最大，为26%;在80 Hz- 5μm振动条件下，焊缝断裂强度增加最小，为39%。在静态制备焊缝的情况下，振荡制备的焊缝晶粒尺寸为38 μm。随着试样厚度从8 mn增加到12 mm，振荡制备的焊缝的拉伸性能值有一些变化。这些值明显大于从固定准备的焊缝获得的值。纵向振动下拉伸性能值的增加归因于晶粒细化、枝晶破碎和晶粒脱离机制。
The effects of specimen thickness on tensile properties of medium carbon steel welds prepared under longitudinal oscillation were investigated. Medium carbon steel workpieces were welded at different frequencies and amplitudes of longitudinal oscillation. Frequencies and amplitudes of oscillations were varied in the range of 0 to 400 Hz and 0 to 40μm, respectively. Specimens were made for tension tests and microstructure examinations from stationary and oscillatory welded workpieces. Test specimens 8mm, 10mm and 12mm thick were tested and yield strength, ultimate tensile strength, percentage of elongation, breaking strength, impact strength and hardness were determined. Metallographic examination of the test specimens was carried out. Yield strength, ultimate tensile strength, breaking strength, improves significantly but percentage of elongation (+5.5%) reduces in oscillatory (longitudinal) prepared welds in comparison to stationary welded test specimens. The maximum increase in tensile properties (yield strength-21%, U.T.S.-26% and breaking strcngth-39%) in oscillatory prepared welds is at 400Hz -5μm and the minimum increase is at 80Hz - 5μm condition. The oscillatory prepared weld grain size in the case of stationary prepared weld was 38 μm. With increase in specimen thickness from 8mn to 12mm there was some change in values of tensile properties for oscillatory prepared welds. The values are significantly more than the values obtained from stationary prepared welds. The increase in values of tensile properties under longitudinal oscillation is attributed to grain refinement, dendrite fragmentation and grain detachment mechanisms.