With the emergence and development of high-speed aircraft, thermal energy storage and nuclear thermal power generation technologies, refractory metals represented by niobium alloy, such as C-103 and NB521, show a good application prospect in rocket combustion chamber, heat dissipation and prevention.
Welding is one of the key technologies affecting the application of niobium alloy. Compared with the general metal, niobium alloy has high melting point, good thermal conductivity, easy oxidation and other characteristics, welding process is easy to produce insufficient depth, poor sealing, surface oxidation and other phenomena, resulting in insufficient structural strength of niobium alloy, difficult to apply.
The purpose of the invention is to provide a welding method for niobium alloy. This method has the advantages of high welding strength, good sealing performance and not easy oxidation, and can realize the reliable connection of niobium alloy.
The above purpose of the invention is mainly achieved through the following technical scheme:
A welding method for niobium alloy comprises the following steps:
Step (1) Splice two niobium alloy plates to be welded to get the gap to be welded;
Step (2) Pre-machining niobium alloy plate along the position of the gap to be welded. The pre-processing method is as follows:
First of all, the width of the gap to be welded between niobium alloy sheet is adjusted to 20-40 times the width of the original gap, and then, along the direction perpendicular to the gap to be welded hole, the diameter of the hole is 40-60 times the width of the original gap, the depth of the hole is the thickness of the niobium alloy plate, and then get the new gap to be welded;
Step (3). Use electron beam to weld the new gap to be welded after step (2).
Step (4) The welding is completed, and the niobium alloy plate welding parts are obtained.
