Li Lihang, Fu Pengfei, Lin Bochao, Wang Xuedong
Key Laboratory of Science and Technology on Power Beam Processes, AVIC Manufacturing Technology Institute, Beijing 100024, China.
Materials (Basel). 2024 Apr 3;17(7):1654. doi: 10.3390/ma17071654.
To enhance welding quality and performance, preheating and post-heating are usually employed on high-temperature materials, concurrently with welding. This is a novel technique in vacuum chamber electron beam welding (EBW). TC17 and TiAlNb alloys are the hot topics in aero-engine parts, and the welding of dissimilar materials is also a broad prospect. To settle welding cracks of TiAlNb, EBW with preheating and post-heating was investigated on TC17 and TiAlNb dissimilar alloy, which improved the manufacturing technology on high-temperature materials. The dissimilar joint no longer had cracks after preheating, which exhibited excellent welding stability and metallurgical homogeneity, and preheating and annealing had an important effect on mechanical properties. The joint strength after 630 °C annealing is higher than that of TC17 alloy base metal (BM) and other annealing temperatures, reaching 1169 MPa at room temperature and 894 MPa at 450 °C tensile condition. The joint plasticity after 740 °C annealing is equivalent to TC17 BM. EBW with preheating improved the microstructure characteristics and enhanced the plasticity of TiAlNb alloy weld and dissimilar joint, which would contribute to the application of TiAlNb alloy and TiAlNb dissimilar parts.
为提高焊接质量和性能，通常在高温材料焊接时采用预热和后热工艺。这是真空室电子束焊接（EBW）中的一项新技术。TC17和TiAlNb合金是航空发动机部件中的热门材料，异种材料焊接也具有广阔前景。为解决TiAlNb的焊接裂纹问题，对TC17和TiAlNb异种合金进行了带预热和后热的电子束焊接研究，改进了高温材料的制造工艺。预热后异种接头不再出现裂纹，表现出优异的焊接稳定性和冶金均匀性，预热和退火对力学性能有重要影响。630℃退火后的接头强度高于TC17合金母材（BM）及其他退火温度，室温下达到1169MPa，450℃拉伸条件下为894MPa。740℃退火后的接头塑性与TC17 BM相当。带预热的电子束焊接改善了TiAlNb合金焊缝和异种接头的微观结构特征，提高了其塑性，这将有助于TiAlNb合金及TiAlNb异种零件的应用。
