The present invention provides a novel heat exchange medium to replace lead. A carbon-steel wire 1A heated in a heating furnace 11 is passed through a bath 12A filled with a liquid-phase Mg—Al—Ca alloy 20 obtained by melting a Mg—Al—Ca alloy in which the main constituent elements are Mg (magnesium), Al (aluminum) and Ca (calcium). When it passes through the bath 12A, the carbon-steel wire 1A, which has been heated for example to about 950° C. in the heating furnace 11, is cooled to about 550° C. The Mg—Al—Ca alloy is non-toxic and has no environmental impact as well.

A method of forming high quality metallurgical bonds in a composite casting is provided. The bonding technology of this invention includes the step of introducing a liquid material to contact the solid components placed in a mold cavity, applying an external field to generate stirring near the solid/liquid interface to wash off bubbles and oxide particles that prevent the liquid material from reacting to the solid component, and causing progressive solidification from the surfaces of the solid component to the liquid to drive away bubbles in the mushy zone near the bonding region. High quality metallurgical bonds are formed within the composite casting after the liquid solidifies. The resultant large composite casting has minimal defects, such as pores and oxides, at the interfaces between the solidified material and the solid objects.

A method of forming high quality metallurgical bonds in a composite casting is provided. The bonding technology of this invention includes the step of introducing a liquid material to contact the solid components placed in a mold cavity, applying an external field to generate stirring near the solid/liquid interface to wash off bubbles and oxide particles that prevent the liquid material from reacting to the solid component, and causing progressive solidification from the surfaces of the solid component to the liquid to drive away bubbles in the mushy zone near the bonding region. High quality metallurgical bonds are formed within the composite casting after the liquid solidifies. The resultant large composite casting has minimal defects, such as pores and oxides, at the interfaces between the solidified material and the solid objects.

A tastable, moldable, and/or extrudable structure using a metallic primary alloy. One or more additives are added to the metallic primary alloy so that in situ galvanically-active reinforcement particles are formed in the melt or on cooling from the melt. The composite contains an optimal composition and morphology to achieve a specific galvanic corrosion rate in the entire composite. The in situ formed galvanically-active particles can be used to enhance mechanical properties of the composite, such as ductility and/or tensile strength. The final casting can also be enhanced by heat treatment, as well as deformation processing such as extrusion, forging, or rolling, to further improve the strength of the final composite over the as-cast material.

A tastable, moldable, and/or extrudable structure using a metallic primary alloy. One or more additives are added to the metallic primary alloy so that in situ galvanically-active reinforcement particles are formed in the melt or on cooling from the melt. The composite contains an optimal composition and morphology to achieve a specific galvanic corrosion rate in the entire composite. The in situ formed galvanically-active particles can be used to enhance mechanical properties of the composite, such as ductility and/or tensile strength. The final casting can also be enhanced by heat treatment, as well as deformation processing such as extrusion, forging, or rolling, to further improve the strength of the final composite over the as-cast material.

The invention is directed to the interventionless activation of wellbore devices using dissolving and/or degrading and/or expanding structural materials. Engineered response materials, such as those that dissolve and/or degrade or expand upon exposure to specific environment, can be used to centralize a device in a wellbore.

The invention is directed to the interventionless activation of wellbore devices using dissolving and/or degrading and/or expanding structural materials. Engineered response materials, such as those that dissolve and/or degrade or expand upon exposure to specific environment, can be used to centralize a device in a wellbore.

Disclosed is a preparation method of a magnesium matrix composite reinforced with SiC particles, belonging to the technical field of metallurgical materials, including the following steps: (1) carrying out oxidation pretreatment on SiC particles; (2) laying a piece of magnesium alloy on a bottom, laying a layer of oxidized SiC particles, then repeating a laying operation of a layer of magnesium alloy and a layer of SiC particles until the magnesium alloy and the SiC particles are completely laid, introducing inert gases, heating and melting, then performing cinder scrapping; (3) cooling to a semisolid temperature of the magnesium alloys for semisolid mechanical stirring, heating, and mechanically stirring again; (4) cooling again to the semisolid temperature of the magnesium alloys, then casting into a blank; and (5) heating the blank to the semisolid temperature of the magnesium alloys and extruding to obtain the magnesium matrix composite reinforced with SiC particles.

The present invention relates to a magnesium alloy sheet and a manufacturing method thereof. In detail, the magnesium alloy sheet includes 0.5 to 3.5 wt % of Al, 0.5 to 1.5 wt % of Zn, 0.1 to 1.0 wt % of Ca, 0.01 to 1.0 wt % of Mn, a remainder of Mg, and other inevitable impurities with respect to an entire 100 wt % of a magnesium alloy sheet, wherein an average crystal grain size of the magnesium alloy sheet is 3 to 15 μm, the magnesium alloy sheet includes a stringer, and a length of the stringer in a rolling direction (RD) is equal to or less than the maximum value of 50 μm.

The present invention relates to a magnesium alloy sheet and a manufacturing method thereof. In detail, the magnesium alloy sheet includes 0.5 to 3.5 wt % of Al, 0.5 to 1.5 wt % of Zn, 0.1 to 1.0 wt % of Ca, 0.01 to 1.0 wt % of Mn, a remainder of Mg, and other inevitable impurities with respect to an entire 100 wt % of a magnesium alloy sheet, wherein an average crystal grain size of the magnesium alloy sheet is 3 to 15 μm, the magnesium alloy sheet includes a stringer, and a length of the stringer in a rolling direction (RD) is equal to or less than the maximum value of 50 μm.