Abstract: The present invention relates to variable melting point solder formulations. The solder is comprised of at least one base metal or base metal alloy, preferably alloyed with at least one melting point depressant metal, such that the solidus point of the solder composition is reduced to an initial solidus temperature. Said base metal or base metal alloy, alloyed with at least one melting point depressant metal is mixed with at least one additive metal or additive metal alloy. When heated to a process temperature above said initial solidus temperature, a reaction occurs between the melting point depressant metal, and the additive metal, such that solidification occurs at the process temperature via the formation of intermetallic phases, effectively increasing the solidus of the base metal, and of the overall solder.

Abstract: The present invention relates to variable melting point solder formulations. The solder is comprised of at least one base metal or base metal alloy, preferably alloyed with at least one melting point depressant metal, such that the solidus point of the solder composition is reduced to an initial solidus temperature. Said base metal or base metal alloy, alloyed with at least one melting point depressant metal is mixed with at least one additive metal or additive metal alloy. When heated to a process temperature above said initial solidus temperature, a reaction occurs between the melting point depressant metal, and the additive metal, such that solidification occurs at the process temperature via the formation of intermetallic phases, effectively increasing the solidus of the base metal, and of the overall solder.

Abstract: A system is disclosed for monitoring and controlling laser cladding process by powder injection in real-time. The invention combines laser cladding technique along with automated direct feedback control to achieve a good quality clad in terms of dimensional and metallurgical characteristics. The system uses optical CCD-based detectors as the feedback system. The optical CCD-based detectors along with a pattern recognition algorithm is used to determine the clad characteristics in real-time. These characteristics are clad's dimensions, solidification rate, and roughness that are fed into a closed loop control system to adjust the laser power and table velocity to produce desired clad quality.

Abstract: Variable melting point solders and brazes having compositions comprising a metal or metal alloy powder having a low melting point with a metal powder having a higher melting point. Upon heating, in-situ alloying occurs between the low and high melting point powders such that solidification occurs at the solder or braze temperature thus creating a new, higher solidus (or melting) temperature with little or no intermetallic formation. A solder comprising Sn powder mixed with a Sn—Bi eutectic powder having a composition of 63 wt % Sn:57 wt % Bi such that the bulk composition of the mixture is 3 wt % Bi has an initial melting point of 140° C. and a re-melt temperature of 220° C. after heating due to in-situ alloying. A composition of Pb powder mixed with a Pb—Sn eutectic powder having a composition of 62 wt % Sn:58 wt % Pb such that the bulk composition of the mixture is 15 wt % Sn has an initial melting point of 183° C. and a re-melt temperature of 250° C.

Abstract: Variable melting point solders and brazes having compositions comprising a metal or metal alloy powder having a low melting point with a metal powder having a higher melting point. Upon heating, in-situ alloying occurs between the low and high melting point powders such that solidification occurs at the solder or braze temperature thus creating a new, higher solidus (or melting) temperature with little or no intermetallic formation. A solder comprising Sn powder mixed with a Sn—Bi eutectic powder having a composition of 63 wt % Sn, 57 wt % Bi such that the bulk composition of the mixture is 3 wt % BS has an initial melting point of 140° C. and a re-melt temperature of 220° C. after heating due to in-situ alloying. A composition of Pb powder mixed with a Pb—Sn eutectic powder having a composition of 62 wt % Sn:58 wt % Pb such that the bulk composition of the mixture is 15 wt % Sn has an initial melting point of 183° C. and a re-melt temperature of 250° C.