Ductile Intermetallic Joints for Heavy Alloys

"Good ballistic performance results when the maximum kinetic energy is delivered to the target. Increasing the weight of the projectile achieves this goal. One reasonable way to enhance the mass behind the nose of the penetrator is to augment its size. Theconflict between increased lethality for large projectiles and limited facilities for producing large penetrators leads to a need to join small pieces of heavy alloy into larger projectiles. Conventional methods to bond heavy alloy either use joiningmaterials that are not strong enough, or require such a high temperature that grain coarsening occurs with a resulting significant decrease in the joint strength. A better bonding method uses an interlayer consisting of high strength multicomponent alloys.These materials possess high strength and ductility. They have good adhesion to the heavy alloy and form strong ductile joints. Bonding of heavy alloy through the use of a high strength alloyed joint occurs at a temperature significantly lower than that ofthe W-Ni-Fe eutectic melting point. This excludes the possibility of grain coarsening and loss of mechanical properties of the heavy alloy. The strength of the joint is measured to be at least 87% of the bulk heavy alloy strength and there are projectedresults that will exceed it."