Peculiarities of crystallization cracks being formed in welding of copper alloys to zirconium and possibility of cracks elimination by microalloying

Studied were the nature and peculiarities of the Cu-Cr-Zr-Ti system alloy destruction in the process of welding along with the possible means to reduce the hot-crack formation tendency by adding traces of boron. The electron microfractography and X-ray spectroscopy methods have been used. The research data have shown that the hot cracks being formed during the welding of the Cu-Cr-Zr-Ti system copper alloys are of an intercrystalline nature. The intergranular destruction is related with the formation of the copper-zirconium eutectics at the grain boundaries. The adding of the boron traces (an admixture extremely inclined to segregate at the grain boundary) to the alloys practically reduces the alloy crack-formation coefficient to a zero. A similar effect may be achieved by the direct introduction of the boron into the seam