In described examples, a transient liquid phase (TLP) metal bonding material includes a first substrate and a base metal layer. The base metal layer is disposed over at least a portion of the first substrate. The base metal has a surface roughness (Ra) of between about 0.001 to 500 nm. Also, the TLP metal bonding material includes a first terminal metal layer that forms an external surface of the TLP metal bonding material. A metal fuse layer is positioned between the base metal layer and the first terminal metal layer. The TLP metal bonding material is stable at room temperature for at least a predetermined period of time.

Aluminum alloy workpieces and/or magnesium alloy workpieces are joined in a solid state weld by use of a reactive material placed, in a suitable form, at the joining surfaces. Joining surfaces of the workpieces are pressed against the interposed reactive material and heated. The reactive material alloys or reacts with the workpiece surfaces consuming some of the surface material in forming a reaction product comprising a low melting liquid that removes oxide films and other surface impediments to a welded bond across the interface. Further pressure is applied to expel the reaction product and to join the workpiece surfaces in a solid state weld bond.

Aluminum alloy workpieces and/or magnesium alloy workpieces are joined in a solid state weld by use of a reactive material placed, in a suitable form, at the joining surfaces. Joining surfaces of the workpieces are pressed against the interposed reactive material and heated. The reactive material alloys or reacts with the workpiece surfaces consuming some of the surface material in forming a reaction product comprising a low melting liquid that removes oxide films and other surface impediments to a welded bond across the interface. Further pressure is applied to expel the reaction product and to join the workpiece surfaces in a solid state weld bond.

A method of bonding a first article to a second article, each article having a respective bond surface. The method comprises interposing a porous interlayer region between the bond surfaces of the first and second articles and subsequently using electrical resistance heating to locally heat the interlayer region under contact pressure to a bonding temperature below the melting temperature of the interlayer and the first and second articles to thereby bond the interlayer to the first and second articles to form a bonded article. The interlayer has a porosity of between approximately 10% and 30%.

A method of bonding a first article to a second article, each article having a respective bond surface. The method comprises interposing a porous interlayer region between the bond surfaces of the first and second articles and subsequently using electrical resistance heating to locally heat the interlayer region under contact pressure to a bonding temperature below the melting temperature of the interlayer and the first and second articles to thereby bond the interlayer to the first and second articles to form a bonded article. The interlayer has a porosity of between approximately 10% and 30%.

A method for manufacturing a bonded substrate is provided, the bonded substrate including a single-crystal semiconductor substrate on a sintered-body substrate that has small warpage after bonding, has good thermal conductivity and small loss at high-frequency region and is suitable for high-frequency devices. Specifically, the method at least includes: applying coating to all of the faces of a sintered-body substrate, so as to obtain a support substrate including at least one layer of amorphous film; and bonding the support substrate and a single-crystal semiconductor substrate via the amorphous film. On a surface of the amorphous film on the support substrate to be bonded with the single-crystal semiconductor substrate, concentration of each of Al, Fe and Ca by ICP-MS method is less than 5.0×10.sup.11 atoms/cm.sup.2, and surface roughness Rms of the surface of the amorphous film is 0.2 nm or less.

A bonding head for performing a thermal compression process including a base body. A bonding heater is disposed on the base body that generates a melting heat. A bonding tool is disposed on the bonding heater that compresses a bonding object against a bonding base while transferring the melting heat to the bonding object to thereby bond the bonding object to the bonding base by the thermal compression process. A heat controller is disposed at the bonding tool, and a thermal conductivity of the heat controller is less than a thermal conductivity of the bonding tool.

A method of manufacturing a hollow aerofoil component (100) for a gas turbine engine (10) comprises using a capping panel (200) to cover a pocket (310) in a pocketed aerofoil body (300). During manufacture, a mandrel (400) is provided to support the capping panel (200) in the correct position. This ensures that the outer surface of the capping panel (200) is located as accurately as possible. This means that the capping panel (200) can be made to be as thin as possible, which in turn reduces weight and material wastage. Remotely detectable elements (700) may be provided to the mandrel (400) to enable the location of the pocket (310) to be accurately determined from outside the aerofoil (100).

A method of manufacturing a hollow aerofoil component (100) for a gas turbine engine (10) comprises using a capping panel (200) to cover a pocket (310) in a pocketed aerofoil body (300). During manufacture, a mandrel (400) is provided to support the capping panel (200) in the correct position. This ensures that the outer surface of the capping panel (200) is located as accurately as possible. This means that the capping panel (200) can be made to be as thin as possible, which in turn reduces weight and material wastage. Remotely detectable elements (700) may be provided to the mandrel (400) to enable the location of the pocket (310) to be accurately determined from outside the aerofoil (100).

Provided is a combined type RFeB-based magnet, including: a first unit magnet; a second unit magnet; and an interface material that bonds the first unit magnet and the second unit magnet, in which the first unit magnet and the second unit magnet are RFeB-based magnets containing a light rare earth element R.sup.L that is at least one element selected from the group consisting of Nd and Pr, Fe, and B, in which the interface material contains at least one compound selected from the group consisting of a carbide, a hydroxide, and an oxide of the light rare earth element R.sup.L, and in which an amount of a heavy rare earth element R.sup.H that is at least one element selected from the group consisting of Dy, Tb and Ho in the second unit magnet is more than that in the first unit magnet.