A rare earth permanent magnet that is high in residual magnetization and coercivity is obtained and includes R and T. A main phase of crystal grains having an Nd.sub.5Fe.sub.17 type crystal structure is included. In an X-ray diffraction profile drawn by performing an XRD measurement for a rare earth permanent magnet, peaks of detected intensity are present in specific ranges. In which the detected intensity of the peak with the highest detected intensity in the range of 41.60<2()<42.80 is set as , the detected intensity of the peak with the highest detected intensity in the range of 34.38<2()<34.64 is set as , and the detected intensity of the peak with the highest detected intensity in the range of 38.70<2()<41.20 is set as , 0.38</<0.70 and 0.45</<0.70 are established. The peak with the highest detected intensity in the range of 34.38<2()<34.64 is a peak derived from the Nd.sub.5Fe.sub.17 type crystal structure.

An oxide superconductor of an embodiment includes an oxide superconductor layer having a continuous Perovskite structure including rare earth elements, barium (Ba), and copper (Cu). The rare earth elements include a first element which is praseodymium, at least one second element selected from the group consisting of neodymium, samarium, europium, and gadolinium, at least one third element selected from the group consisting of yttrium, terbium, dysprosium, and holmium, and at least one fourth element selected from the group consisting of erbium, thulium, ytterbium, and lutetium. When the number of atoms of the first element is N(PA), the number of atoms of the second element is N(SA), and the number of atoms of the fourth element is N(CA), 1.5(N(PA)+N(SA))N(CA) or 2(N(CA)N(PA))N(SA) is satisfied.

An oxide superconductor of an embodiment includes an oxide superconductor layer having a continuous Perovskite structure including rare earth elements, barium (Ba), and copper (Cu). The rare earth elements include a first element which is praseodymium, at least one second element selected from the group consisting of neodymium, samarium, europium, and gadolinium, at least one third element selected from the group consisting of yttrium, terbium, dysprosium, and holmium, and at least one fourth element selected from the group consisting of erbium, thulium, ytterbium, and lutetium. When the number of atoms of the first element is N(PA), the number of atoms of the second element is N(SA), and the number of atoms of the fourth element is N(CA), 1.5(N(PA)+N(SA))N(CA) or 2(N(CA)N(PA))N(SA) is satisfied.

A magnetic material and an inductor capable of attaining both higher magnetic permeability and improved DC superposition characteristics. A composite magnetic material contains metal magnetic particles, in which the metal magnetic particles include first particles having a median diameter D.sub.50 of 1.3 m or more and 5.0 m or less (i.e., from 1.3 m to 5.0 m), and second particles having a median diameter D.sub.50 larger than the first particles. The first and second particles each include a core portion made of a metal magnetic material, and an insulating film provided on a surface of the core portion. The insulating film of the second particles has an average thickness of 40 nm or more and 100 nm or less (i.e., from 40 nm to 100 nm). The insulating film of the first particles has an average thickness smaller than that of the insulating film of the second particles.

A magnetic material and an inductor capable of attaining both higher magnetic permeability and improved DC superposition characteristics. A composite magnetic material contains metal magnetic particles, in which the metal magnetic particles include first particles having a median diameter D.sub.50 of 1.3 m or more and 5.0 m or less (i.e., from 1.3 m to 5.0 m), and second particles having a median diameter D.sub.50 larger than the first particles. The first and second particles each include a core portion made of a metal magnetic material, and an insulating film provided on a surface of the core portion. The insulating film of the second particles has an average thickness of 40 nm or more and 100 nm or less (i.e., from 40 nm to 100 nm). The insulating film of the first particles has an average thickness smaller than that of the insulating film of the second particles.

An R-T-B based permanent magnet includes main phase grains composed of R.sub.2T.sub.14B type compound. R is a rare earth element. T is iron group element(s) essentially including Fe or Fe and Co. B is boron. An average grain size of the main phase grains is 0.8 m to 2.8 m. The R-T-B based permanent magnet contains at least C and Ga in addition to R, T, and B. B is contained at 0.71 mass % to 0.86 mass %. C is contained at 0.13 mass % to 0.34 mass %. Ga is contained at 0.40 mass % to 1.80 mass %. A formula (1) of 0.14[C]/([B]+[C])0.30 is satisfied, where [B] is a B content represented by atom %, and [C] is a C content represented by atom %.

An R-T-B based sintered magnet includes R, T, and B. R represents a rare earth element. T represents a metal element other than rare earth elements including at least Fe, Cu, Mn, Al, Co, Ga, and Zr. B represents boron or boron and carbon. With respect to 100 mass % of a total mass of the R-T-B based sintered magnet, a content of R is 28.0 to 31.5 mass %, a content of Cu is 0.04 to 0.50 mass %, a content of Mn is 0.02 to 0.10 mass %, a content of Al is 0.15 to 0.30 mass %, a content of Co is 0.50 to 3.0 mass %, a content of Ga is 0.08 to 0.30 mass %, a content of Zr is 0.10 to 0.25 mass %, and a content of B is 0.85 to 1.0 mass %.

An R-T-B based sintered magnet includes R, T, and B. R represents a rare earth element. T represents a metal element other than rare earth elements including at least Fe, Cu, Mn, Al, Co, Ga, and Zr. B represents boron or boron and carbon. With respect to 100 mass % of a total mass of the R-T-B based sintered magnet, a content of R is 28.0 to 31.5 mass %, a content of Cu is 0.04 to 0.50 mass %, a content of Mn is 0.02 to 0.10 mass %, a content of Al is 0.15 to 0.30 mass %, a content of Co is 0.50 to 3.0 mass %, a content of Ga is 0.08 to 0.30 mass %, a content of Zr is 0.10 to 0.25 mass %, and a content of B is 0.85 to 1.0 mass %.

According to an embodiment, a composite permanent magnet includes a matrix of magnetically hard phase grains having an average grain size of 10 nm to 50 m; and magnetically soft phase grains embedded within the matrix, and having an average grain size of at least 50 nm, each grain having an elongated shape with an aspect ratio of at least 2:1. According to another embodiment, a composite permanent magnet includes a matrix of magnetically hard phase grains having an average grain size of 10 nm to 50 m; and magnetically soft phase grains embedded within the matrix, and having an average grain width of at least 50 nm, an average grain height of 20 to 500 nm, and an aspect ratio of at least 2:1. According to yet another embodiment, a method of forming a composite permanent magnet is also provided.

According to an embodiment, a composite permanent magnet includes a matrix of magnetically hard phase grains having an average grain size of 10 nm to 50 m; and magnetically soft phase grains embedded within the matrix, and having an average grain size of at least 50 nm, each grain having an elongated shape with an aspect ratio of at least 2:1. According to another embodiment, a composite permanent magnet includes a matrix of magnetically hard phase grains having an average grain size of 10 nm to 50 m; and magnetically soft phase grains embedded within the matrix, and having an average grain width of at least 50 nm, an average grain height of 20 to 500 nm, and an aspect ratio of at least 2:1. According to yet another embodiment, a method of forming a composite permanent magnet is also provided.