高压环境对直流正接GMAW电弧作用机理研究

项目名称： 高压环境对直流正接GMAW电弧作用机理研究

项目编号： No.51475102

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 机械、仪表工业

项目作者： 高洪明

作者单位： 哈尔滨工业大学

项目金额： 83万元

中文摘要： 随着陆地油气资源的日渐枯竭，资源开发向深海进军已成为必然趋势。本项目以深水（>100米）海洋工程焊接修复为背景，以X65管线钢为试验材料，针对水下高压干法GMAW焊接工艺存在的电弧不稳定、飞溅多等问题，开展高压环境对直流正接GMAW电弧影响机理研究。从高压环境GMAW焊接电弧行为、熔滴过渡特性等角度，对比分析不同环境压力、不同极性接法GMAW电弧的特点，揭示高压环境对直流正接GMAW焊接过程的影响机制。根据电弧形态、熔滴过渡形式、焊接焊缝成形等定义描述焊接过程稳定性的评价函数，通过物理模拟实验或数值模拟，得出环境压力与该评价函数之间的解析关系或数值关系。在掌握直流正接GMAW焊接物理机制的基础上，通过实验建立焊接过程中各个参数对焊接过程稳定性及焊接质量的影响规律，给出该工艺优化参数的选择原则，为高压干法GMAW水下焊接的实际应用提供理论支撑。

中文关键词： GMAW；环境压力；电弧特性；熔滴过渡；光谱诊断

英文摘要： With the gradual depletion of oil and gas resources of the land，deep sea exploration and mining has become an inevitable trend. This project is based on the background of welding repairing of Ocean Engineering (deeper than 100 meters); the X65 pipe steel is selected as the experimental materials. In order to solve the arc instability and spatter problem of dry hyperbaric GMAW process, the mechanism of DCEN GMA under high pressure is investigated. From the viewpoint of the GMA characteristics and metal transfer under high pressure environment, the pressure, the polarity of the power source is also considered. Then try to reveal the mechanism of the pressure influences on DCEN GMAW process. According to the arc shape, metal transfer mode and the weld formation, an evaluation function is selected to describe the process stability. Through the physical experiments or numerical simulation, the analytical or numerical relationship between the evaluation function and the pressure is obtained. On the base of understanding the mechanism, the welding experiments is carried out to achieved the influence laws of the welding parameters. An rule is given to fit the parameters, and provided the theoretical support to the application of dry hyperbaric GMAW process.

英文关键词： GMAW;Pressure;Arc characteristic;Metal transfer;Spectroscopy diagnosis