Review of the weldability window concept and equations for explosive welding

Explosive cladding/welding is usually considered a solid state process in which the detonation of a certain amount of an explosive composition is used to accelerate one of the materials to be weld against the other in order to promote a high velocity oblique collision that will be responsible for bonding the materials. The conditions that should be met to achieve good welds define what is called as a weldability window or criteria. A weldability criteria based on the collision point velocity (V_c) and on the collision angle (β) is the most used today. In the β-V_c space the weldability window is defined by four lines or limits. Despite of its wide used in explosive welding works, neither the concepts behind those limits neither the equations used to define them in the β-V_c space are particularly clear. Contradictory concepts, and equations with undefined variables or parameters, are commonly found in the literature. This paper aims to clarify those concepts and equations through an integrated description of the weldability limits and a reviewed presentation of the associated equations with the variables and parameters, including their units, clearly defined. The reviewed concepts and equations are then used for the description of the explosive weld of stainless steel to carbon steel in cylindrical configuration.