A Sm—Fe—N magnet includes Sm—Fe—N particles, wherein an inter-particle metal phase is present between at least two of the Sm—Fe—N particles, an average particle diameter of the Sm—Fe—N particles is less than 2.0 μm, and a percentage of the Sm—Fe—N particles having an aspect ratio of 2.0 or more is 10% or less, the inter-particle metal phase includes a Fe.sub.3Zn.sub.10 phase and an α-Fe phase in a particle form, and in the inter-particle metal phase, an area ratio of the Fe.sub.3Zn.sub.10 phase is 80% or more.

A polycrystalline diamond construction has a body of polycrystalline diamond (PCD) material; and a cemented carbide substrate bonded to the body of polycrystalline material along an interface. The cemented carbide substrate has tungsten carbide particles bonded together by a binder material, the binder material comprising Co; and the tungsten carbide particles form at least around 70 weight percent and at most around 95 weight percent of the substrate. The cemented carbide substrate has a bulk volume, the bulk volume of the cemented carbide substrate having at least around 0.1 vol. % of inclusions of free carbon having a largest average size in any one or more dimensions of less than around 40 microns.

A polycrystalline diamond construction has a body of polycrystalline diamond (PCD) material; and a cemented carbide substrate bonded to the body of polycrystalline material along an interface. The cemented carbide substrate has tungsten carbide particles bonded together by a binder material, the binder material comprising Co; and the tungsten carbide particles form at least around 70 weight percent and at most around 95 weight percent of the substrate. The cemented carbide substrate has a bulk volume, the bulk volume of the cemented carbide substrate having at least around 0.1 vol. % of inclusions of free carbon having a largest average size in any one or more dimensions of less than around 40 microns.

A method of forming a cutting element comprises disposing diamond particles in a container and disposing a metal powder on a side of the diamond particles. The diamond particles and the metal powder are sintered so as to form a polycrystalline diamond material and a low-carbon steel material comprising less than 0.02 weight percent carbon and comprising an intermetallic precipitate on a side of the polycrystalline diamond material. Related cutting elements and earth-boring tools are also disclosed.

A method of forming a cutting element comprises disposing diamond particles in a container and disposing a metal powder on a side of the diamond particles. The diamond particles and the metal powder are sintered so as to form a polycrystalline diamond material and a low-carbon steel material comprising less than 0.02 weight percent carbon and comprising an intermetallic precipitate on a side of the polycrystalline diamond material. Related cutting elements and earth-boring tools are also disclosed.

A polycrystalline diamond construction has a body of polycrystalline diamond (PCD) material; and a cemented carbide substrate bonded to the body of polycrystalline material along an interface. The cemented carbide substrate includes tungsten carbide particles bonded together by a binder material, the binder material comprising an alloy of Co, Ni and Cr; and the tungsten carbide particles form at least around 70 weight percent and at most around 95 weight percent of the substrate. The cemented carbide substrate has a bulk volume, the bulk volume of the cemented carbide substrate has at least around 0.1 vol. % of inclusions of free carbon having a largest average size in any one or more dimensions of less than around 40 microns.

A polycrystalline diamond construction has a body of polycrystalline diamond (PCD) material; and a cemented carbide substrate bonded to the body of polycrystalline material along an interface. The cemented carbide substrate includes tungsten carbide particles bonded together by a binder material, the binder material comprising an alloy of Co, Ni and Cr; and the tungsten carbide particles form at least around 70 weight percent and at most around 95 weight percent of the substrate. The cemented carbide substrate has a bulk volume, the bulk volume of the cemented carbide substrate has at least around 0.1 vol. % of inclusions of free carbon having a largest average size in any one or more dimensions of less than around 40 microns.

A bonding sheet includes a copper foil and sinterable bonding films formed on both faces of the copper foil. The bonding films each contain copper particles and a solid reducing agent. The bonding sheet is used to bond to a target object to be bonded having at least one metal selected from gold, silver, copper, and nickel on a surface thereof. A bonded structure includes: a bonded object having at least one metal selected from gold, silver, copper, and nickel on a surface thereof; a copper foil; and a bonding layer including a sintered structure of copper particles; and the bonded object and the copper foil are electrically connected to each other via the bonding layer.

A bonding sheet includes a copper foil and sinterable bonding films formed on both faces of the copper foil. The bonding films each contain copper particles and a solid reducing agent. The bonding sheet is used to bond to a target object to be bonded having at least one metal selected from gold, silver, copper, and nickel on a surface thereof. A bonded structure includes: a bonded object having at least one metal selected from gold, silver, copper, and nickel on a surface thereof; a copper foil; and a bonding layer including a sintered structure of copper particles; and the bonded object and the copper foil are electrically connected to each other via the bonding layer.

A polycrystalline super hard construction has a first region having a body of thermally stable polycrystalline super hard material having a plurality of intergrown grains of super hard material; a second region forming a substrate having a hard phase and a binder phase; and a third region interposed between the first and second regions. The third region includes a composite material having a first phase comprising a plurality of non-intergrown grains of super hard material, and a matrix material. A fourth region interposed between the second and third region has a major proportion having one or more components of the binder material of the second region, and one or more reaction products between the binder material of the second region and one or more components of the third region.