Solder paste consisting of 85 to 92% by weight of a tin-based solder and 8 to 15% by weight of a flux, wherein the flux comprises i) 30 to 50% by weight, based on its total weight, of a combination of at least two optionally modified natural resins, ii) 5 to 20% by weight, based on its total weight, of at least one low-molecular carboxylic acid; and iii) 0.4 to 10% by weight, based on its total weight, of at least one amine, and wherein the combination of the optionally modified natural resins has an integral molecular weight distribution of 45 to 70% by area in the molecular weight range of 150 to 550 and of 30 to 55% by area in the molecular weight range of >550 to 10,000 in the combined GPC.

Solder paste consisting of 85 to 92% by weight of a tin-based solder and 8 to 15% by weight of a flux, wherein the flux comprises i) 30 to 50% by weight, based on its total weight, of a combination of at least two optionally modified natural resins, ii) 5 to 20% by weight, based on its total weight, of at least one low-molecular carboxylic acid; and iii) 0.4 to 10% by weight, based on its total weight, of at least one amine, and wherein the combination of the optionally modified natural resins has an integral molecular weight distribution of 45 to 70% by area in the molecular weight range of 150 to 550 and of 30 to 55% by area in the molecular weight range of >550 to 10,000 in the combined GPC.

The present invention discloses an Al.sub.2O.sub.3-based ceramic welding sealing component and a preparation method thereof, and relates to the technical field of metalized ceramic processing. The Al.sub.2O.sub.3-based ceramic welding sealing component disclosed in the present invention comprises a ceramic matrix and a metallized layer. The ceramic matrix is made from raw materials such as an inorganic fiber-aluminum oxide 3D network matrix, yttrium oxide, silicon oxide, titanium oxide, an additive, a binder and a dispersant, through steps such as preparation of the inorganic fiber-aluminum oxide 3D network matrix, mixing, pelletizing, primary sintering and secondary sintering; and the raw materials of the metallized layer comprise titanium powder, tungsten powder, molybdenum oxide, boron oxide, yttrium oxide and an organic binder. Al.sub.2O.sub.3-based ceramic welding sealing component provided by the present invention has high efficiency of space filling and tensile strength, excellent tensile strength, toughness and high-temperature resistance.

The present invention discloses an Al.sub.2O.sub.3-based ceramic welding sealing component and a preparation method thereof, and relates to the technical field of metalized ceramic processing. The Al.sub.2O.sub.3-based ceramic welding sealing component disclosed in the present invention comprises a ceramic matrix and a metallized layer. The ceramic matrix is made from raw materials such as an inorganic fiber-aluminum oxide 3D network matrix, yttrium oxide, silicon oxide, titanium oxide, an additive, a binder and a dispersant, through steps such as preparation of the inorganic fiber-aluminum oxide 3D network matrix, mixing, pelletizing, primary sintering and secondary sintering; and the raw materials of the metallized layer comprise titanium powder, tungsten powder, molybdenum oxide, boron oxide, yttrium oxide and an organic binder. Al.sub.2O.sub.3-based ceramic welding sealing component provided by the present invention has high efficiency of space filling and tensile strength, excellent tensile strength, toughness and high-temperature resistance.

The present disclosure is directed to a tubular welding electrode with a sheath encapsulating a flux core, where the sheath comprises a number of added pores. The added pores may provide escape paths for the outgassing of moisture and hydrocarbons from the flux core when the tubular welding electrode is baked. In addition, the added pores may be used to hold a liquid, such as a lubricant. The added pores may be introduced using a process such as laser drilling or chemical etching, and may be added to a strip of sheath material prior to forming the strip into a tubular welding electrode.

A TIG welding flux for chromium-molybdenum steel is used to form a weld bead with high mechanical strength and high fracture toughness between two chromium-molybdenum steel workpieces. The TIG welding flux for chromium-molybdenum steel includes 30-44 wt % of silicon dioxide (SiO.sub.2), 20-35 wt % of manganese(IV) oxide (MnO.sub.2), 14-24 wt % of chromium(III) oxide (Cr.sub.2O.sub.3), 9-19 wt % of nickel(III) oxide (Ni.sub.2O.sub.3), 7-14 wt % of molybdenum trioxide (MoO.sub.3) and 5-10 wt % of calcium fluoride (CaF.sub.2).

Compositions and methods for coupling metals to aluminum surfaces are provided. The compositions are prepared as aqueous solutions or suspensions, and can be applied to the aluminum surface using conventional printing techniques. Rheology of the printable composition can be adjusted to provide a gel or a cream. Curing steps, if necessary, are performed at low temperatures that are compatible with plastic/polymer components of mass produced devices, such as aluminum RFID antennae.

The present disclosure provides a device and method for manufacturing a coated welding rod. The device for manufacturing a coated welding rod includes a grabbing device, a heating device, and a flux storage device. The heating device is configured to heat a welding rod in the grabbing device. A flux in granular form is stored in the flux storage device, the grabbing device is configured to transport the heated welding rod into the flux storage device, and the heated welding rod is configured to heat the flux surrounding the welding rod into a viscous glassy state so that the flux in the viscous glassy state adheres to the surface of the welding rod. The heated welding rod enables the granular flux to be formed into a viscous glassy state so that the flux can be adhered directly to the surface of the welding rod.

The present disclosure provides a device and method for manufacturing a coated welding rod. The device for manufacturing a coated welding rod includes a grabbing device, a heating device, and a flux storage device. The heating device is configured to heat a welding rod in the grabbing device. A flux in granular form is stored in the flux storage device, the grabbing device is configured to transport the heated welding rod into the flux storage device, and the heated welding rod is configured to heat the flux surrounding the welding rod into a viscous glassy state so that the flux in the viscous glassy state adheres to the surface of the welding rod. The heated welding rod enables the granular flux to be formed into a viscous glassy state so that the flux can be adhered directly to the surface of the welding rod.

Provided are flux for resin flux cored solder, flux for flux-coated solder, resin flux cored solder using the flux for resin flux cored solder, flux-coated solder using the flux for flux-coated solder, and a soldering method, which have low residue and are excellent in processability. The flux for resin flux cored solder or flux-coated solder contains a solid solvent in an amount of 70 wt % or more and 99.5 wt % or less, and an activator in an amount of 0.5 wt % or more and 30 wt % or less.