工业纯钛TA1管道的焊接

通过对工业纯钛ＴＡ１管道的焊接性分析，提出了控制微裂纹等焊接缺陷的工艺措施。采用钨极氩弧焊，成功地焊接了耐酸条件下的ＴＡ１管道。     

Calculation on the solid solution forming enthalpies of Re-Mo-Ti gradient alloy in thermodynamics

The idea about preparation of Re-Mo-Ti alloy is put forward because of applications of Re and Mo-Re alloys in aerospace. Basing on the thermodynamics theory, the feasibility of developing a new high temperature alloy Re-Mo-Ti is investigated. The solid solution forming enthalpies of binary alloys Re-Ti, Mo-Ti and Mo-Re are calculated with the Miedema thermodynamics theory. The Miedema theory of binary alloy can be used in ternary alloy through Kohler model or Toop model. The calculated results show that the forming enthalpies of binary alloys Re-Ti, Ti-Mo and Re-Mo are negative, which indicates that binary alloys Re-Ti, Ti-Mo and Re-Mo can form solid solution in wider component area. The forming enthalpies of Re-Mo-Ti ternary alloy are still negative and smaller than those of binary alloys Re-Ti, Ti-Mo or Re-Mo, which indicates it is possible to form large solid solution graph area among ternary alloys of Ti, Mo, Re elements. It is feasible to develop a new high temperature material in thermodynamics, in this material Re-Mo-Ti solid solution as base phase, and the Ti₅Re₂₄ intermetallic compounds or interphase ω (Ti₄Mo₃) as strengthening phase.