The application relates to a low-silver solder for welding an electric vacuum device and a preparation method thereof, The low-silver solder for welding the electric vacuum device is characterized by consisting of Ag, Cu, Ni and a trace element R, wherein the low-silver solder comprises the following components in percentage by mass: 65-71% of Ag, 0-0.1% of Ni, 0-0.1% of trace element R and the balance of Cu; the trace element R consists of one or more of P, Sc, Be, Zr and La. A method of producing the low silver solder, characterized by the steps of: Ag, Cu except from copper foil and Ni are evenly preset in a smelting crucible, the trace elements wrapped by the copper foil are placed above main raw materials consisting of the Ag,Cu except from copper foil and Ni, then smelting and casting are carried out by adopting a vacuum induction smelting furnace, the vacuum degree of a furnace body reaches 10.sup.−1 Pa during smelting and casting, and finally a strip material or a wire materialis prepared by a post treatment process, which has the advantages of good processing performance, good fluidity, low air content in a welding line and excellent thermal stability.

The application relates to a low-silver solder for welding an electric vacuum device and a preparation method thereof, The low-silver solder for welding the electric vacuum device is characterized by consisting of Ag, Cu, Ni and a trace element R, wherein the low-silver solder comprises the following components in percentage by mass: 65-71% of Ag, 0-0.1% of Ni, 0-0.1% of trace element R and the balance of Cu; the trace element R consists of one or more of P, Sc, Be, Zr and La. A method of producing the low silver solder, characterized by the steps of: Ag, Cu except from copper foil and Ni are evenly preset in a smelting crucible, the trace elements wrapped by the copper foil are placed above main raw materials consisting of the Ag,Cu except from copper foil and Ni, then smelting and casting are carried out by adopting a vacuum induction smelting furnace, the vacuum degree of a furnace body reaches 10.sup.−1 Pa during smelting and casting, and finally a strip material or a wire materialis prepared by a post treatment process, which has the advantages of good processing performance, good fluidity, low air content in a welding line and excellent thermal stability.

A ceramic circuit substrate having high bonding performance and excellent thermal cycling resistance properties, wherein a ceramic substrate and a copper plate are bonded by a braze material containing Ag and Cu, at least one active metal component selected from Ti and Zr, and at least one element selected from among In, Zn, Cd, and Sn, wherein a braze material layer, after bonding, has a continuity ratio of 80% or higher and a Vickers hardness of 60 to 85 Hv.

A ceramic circuit substrate having high bonding performance and excellent thermal cycling resistance properties, wherein a ceramic substrate and a copper plate are bonded by a braze material containing Ag and Cu, at least one active metal component selected from Ti and Zr, and at least one element selected from among In, Zn, Cd, and Sn, wherein a braze material layer, after bonding, has a continuity ratio of 80% or higher and a Vickers hardness of 60 to 85 Hv.

The present invention discloses silver alloy composition consisting of at least 90.0% silver, 0.01-1.5% by weight of each of zirconium, magnesium, titanium and the balance copper with improved mechanical properties. The alloying metal in silver alloy impart both high “as cast” and “60% cold worked” hardness with workable springiness, reduced specific gravity and is resistant to wear and tear.

The present invention discloses silver alloy composition consisting of at least 90.0% silver, 0.01-1.5% by weight of each of zirconium, magnesium, titanium and the balance copper with improved mechanical properties. The alloying metal in silver alloy impart both high “as cast” and “60% cold worked” hardness with workable springiness, reduced specific gravity and is resistant to wear and tear.

A method for manufacturing a metal-ceramic substrate (1) includes providing a ceramic layer (10), a metal layer (20) and a solder layer (30) coating the ceramic layer (10) and/or the metal layer (20) and/or the solder layer (30) with an active metal layer (40), arranging the solder layer (30) between the ceramic layer (10) and the metal layer (20) along a stacking direction (S), forming a solder system (35) comprising the solder layer and the active metal layer (40), wherein a solder material of the solder layer (30) is free of a melting point lowering material and bonding the metal layer (20) to the ceramic layer (10) via the solder system (35) by means of an active solder process.

A ceramic circuit substrate having high bonding performance and excellent thermal cycling resistance properties, having a circuit pattern provided on a ceramic substrate with a braze material layer interposed therebetween, and a protruding portion formed by the braze material layer protruding from the outer edge of the circuit pattern, wherein: the braze material layer includes Ag, Cu, Ti, and Sn or In; and an Ag-rich phase is formed continuously for 300 μm or more, towards the inside, from an outer edge of the protruding portion, along a bonding interface between the ceramic substrate and the circuit pattern, and has a bonding void ratio of 1.0% or less.

A layered structure for forming charging terminals for high power applications. In some embodiments, the layered structure may include a substrate and a contact layer disposed over at least a portion of the substrate. The substrate may have a conductivity greater than 40% International Annealed Copper Standard (IACS). The contact layer may demonstrate a coefficient of friction of less than 1.4, such as from 0.1 to 1.4, as measured in accordance with American Society of Testing and Materials (ASTM) G99-17. The contact layer may include a precious-metal-based alloy, such as a silver-samarium alloy.

A layered structure for forming charging terminals for high power applications. In some embodiments, the layered structure may include a substrate and a contact layer disposed over at least a portion of the substrate. The substrate may have a conductivity greater than 40% International Annealed Copper Standard (IACS). The contact layer may demonstrate a coefficient of friction of less than 1.4, such as from 0.1 to 1.4, as measured in accordance with American Society of Testing and Materials (ASTM) G99-17. The contact layer may include a precious-metal-based alloy, such as a silver-samarium alloy.