1Cr17Ni13Mo2Ti焊缝冲击韧性及冷弯性能研究

On impact and cold bend properties of 1Cr17Ni13Mo2Ti steel weld metal

关键词:  奥氏体焊缝  韧性  氧  δ铁素体

Key words:  austenitic weld metal  toughness  oxygen  δ-fcrrite

摘要:

本文进行了A212、A207焊条手工焊接和TIG焊接1Cr17Ni13Mo2Ti焊缝的冲击韧性和冷弯性能试验,分析了焊缝显微组织和冲击断口,测定了焊缝中的δ铁素体和氧含量。研究结果表明,用低氢型A207焊条和TIG焊焊接的焊缝中氧含量降低,夹杂物含量减少,焊缝中δ铁素体含量减少,其分布和形态明显改善,因而焊缝在延性断裂过程中裂纹形核核心减少,韧窝尺寸增大,塑性变形程度增大,断裂吸收功增加,焊缝的冲击韧性和冷弯性能明显改善。

Abstract:

The impact and cold bend tests of 1Cr17Ni13Mo2Ti steel weld metals welded with A212, A207 coated electrodes and TIG process have been carried out. The microstructures of the weld metals and the appearances of the fractured specimens have been investigated. The δ-fcrritc content and oxygen in the weld metals have been measured. In the weld metals welded with the low-hydrogen type A207 covered electrode and TIG process, there arc less oxygen and δ-ferritc than that in the weld metal welded with the A212 coated electrode. The morphology and distribution of δ-ferrite in the former arc improved, and the inclusion particles decrease. As a result, when the former fractures, there is few microcrack originated site and the size of the dimples increase, the weld metal has a strong ability for plastic deformation. So the absorbed energy in fracturing raises and the impact toughness and cold bend property of the weld metal are obviously improved.