铝热焊用一次性坩埚的研制

分析一次性坩埚所选的原沙、树脂砂和粘结剂等原料的参数。研究树脂砂的强度、发气量、表面稳定性、耐热性等性能,保证树脂砂的适用性。使用成型的树脂自硬砂一次性坩埚进行焊接,焊接接头的硬度平均为288HB,力学性能主要参数Rm为790MPa,静弯平均为1500kN。根据TB/T1632 91要求对焊接接头的硬度、力学性能、静弯强度进行试验。分析焊接接头夹杂物情况和焊缝金相组织形貌,并与使用镁质坩埚的情况进行对比。试验结果显示,研制的一次性坩埚可以满足铝热焊接使用。

Development of a Single-use Crucible for Alumino-thermit Welding

Parameters of raw materials selected for making the single-use crucible such as orthosand, resin sand and bonding agent are analyzed. Performances such as strength, air release, surface stability and thermal resistance of resin sand are studied to ensure the suitability of resin sand. A single-use crucible of formed resin self-hardening sand is used for welding with the average hardness of the welding joints being 288 HB, the main mechanical parameter Rm 790 MPa and average stationary bending 1 500 kN. Tests are conducted on the hardness, mechanical performance and stationary bending strength of the welding joints according to TB/T1632-91. Impurities of welding joints and metallic phase appearance of welding seam are analyzed and a comparison is made with the welding joist made with a magnesium crucible. Test results show that the single-use crucible developed meets the requirements for alumino thermite welding.