Abstract: The present invention provides a method for producing a polydioxolane, which includes polymerizing a 1,3-dioxolane compound represented by the formula (1) in the presence of a cationic catalyst and a sterically hindered phenol in an amount of 10 to 1,500 ppm, based on the 1,3-dioxolane compound. In the formula (1), R1 to R6 are the same or difference and each independently represents a hydrogen atom, an alkyl group, an aryl group, a hydroxyalkyl group, an alkyloxy group, or an aryloxy group.

Abstract: A method for forming a surface layer, the purpose thereof is to form a high erosion resistant film. The method for forming a surface layer includes: arranging a member (2) in a machining fluid (3); and forming the surface layer including silicon by spacing a silicon electrode (1) from the member (2) at a predetermined distance, and by supplying silicon component from the silicon electrode (1) to the member side by applying a predetermined voltage and generating electric discharge, and an iron-based metal texture including silicon of 3 to 11 wt % is formed at a thickness of 5 to 10 ?m at a portion to be treated by repetitively generating a electric discharge pulse in which a time integration value of a current value of the electric discharge pulse is in a range of 30 A·?s to 80 A·?s.

Abstract: The present invention provides a method for producing a polydioxolane, which includes polymerizing a 1,3-dioxolane compound represented by the formula (1) in the presence of a cationic catalyst and a sterically hindered phenol in an amount of 10 to 1,500 ppm, based on the 1,3-dioxolane compound. In the formula (1), R1 to R6 are the same or difference and each independently represents a hydrogen atom, an alkyl group, an aryl group, a hydroxyalkyl group, an alkyloxy group, or an aryloxy group.

Abstract: A method of manufacturing an electrode for electrical-discharge surface treatment includes increasing oxygen content in the powder; mixing the powder, in which the oxygen content is increased, with an organic binder and a solvent to prepare a liquid mixture; granulating the powder in the liquid mixture to form granulated powder; and forming the granulated powder to prepare a compact in which an oxygen concentration ranges from 4 weight % to 16 weight %.

Abstract: A discharge surface treatment apparatus generates a pulsed discharge between poles, that is, between a discharge electrode and a workpiece, and the discharge electrode is obtained by compression-molding of any one of a metal powder, a powder of a metal compound, and a powder of ceramics or a mixture thereof. The apparatus forms a film made of an electrode material or the like on a workpiece surface by thermal energy due to the discharge. The apparatus includes: a capacitor that is connected to any one of the discharge electrode and the workpiece at one end; and a parallel circuit of a resistor and a diode, which is provided between another one of the discharge electrode and the workpiece and another end of the capacitor via a connection line.

Abstract: An electrical discharge surface treatment method for forming a coating film by generating a pulsed electrical discharge between an electrode and a workpiece in working fluid or gas using a green compact obtained by molding metal powder or metal alloy powder or a molded body obtained by heating the green compact as the electrode, and by melting an electrode material by an energy of the pulsed electrical discharge, forming a coating of the electrode material or a coating of a material obtained by a reaction of the electrode material by the energy of the pulsed electrical discharge on a surface of the workpiece, the electrical discharge surface treatment method includes generating the pulsed electrical discharge by mixing together two or more types of pulsed electrical discharges having different energies.

Abstract: A method for forming a surface layer, the purpose thereof is to form a high erosion resistant film. The method for forming a surface layer includes: arranging a member (2) in a machining fluid (3); and forming the surface layer including silicon by spacing a silicon electrode (1) from the member (2) at a predetermined distance, and by supplying silicon component from the silicon electrode (1) to the member side by applying a predetermined voltage and generating electric discharge, and an iron-based metal texture including silicon of 3 to 11 wt % is formed at a thickness of 5 to 10 ?m at a portion to be treated by repetitively generating a electric discharge pulse in which a time integration value of a current value of the electric discharge pulse is in a range of 30 A·?s to 80 A·?s.

Abstract: Using electrical discharge surface treatment of moving an electrode material to a work piece by repeatedly generating pulsed electrical discharge between an electrode for electrical discharge surface treatment (1) containing Si as a main component and a work piece (2) surface in order to form a surface layer excellent in an anti-corrosion property and an anti-erosion property which is useful in applications to anti-corrosion and anti-erosion parts, a surface layer formed with an amorphous structure, in which an Si component is contained in a range of 3 to 11 wt % and which has a thickness of 5 to 10 ?m, is formed on the work piece (2) surface.

Abstract: A discharge surface treatment apparatus generates a pulsed discharge between poles, that is, between a discharge electrode and a workpiece, and the discharge electrode is obtained by compression-molding of any one of a metal powder, a powder of a metal compound, and a powder of ceramics or a mixture thereof. The apparatus forms a film made of an electrode material or the like on a workpiece surface by thermal energy due to the discharge. The apparatus includes: a capacitor that is connected to any one of the discharge electrode and the workpiece at one end; and a parallel circuit of a resistor and a diode, which is provided between another one of the discharge electrode and the workpiece and another end of the capacitor via a connection line.

Abstract: An electrode for electric-discharge surface treatment, which is used in the electric-discharge surface treatment in which pulsed electric discharge is generated between the electrode and a base material in a machining fluid or in the air by using a green compact, which is formed by compressing powder of an electrode material, as the electrode, and by using energy of the electric discharge, a coating including the electrode material or a reaction product of the electrode material reacted by the electric discharge energy is formed on a surface of a base material, wherein a mixture of Si powder having an average particle diameter of not less than 0.3 ?m and not more than 10 ?m and hard material powder having an average particle diameter of not less than 0.3 ?m and not more than 10 ?m is used as the electrode material.

Abstract: There is an electrical discharge surface treatment method of forming a surface layer on a work piece surface by making pulsed electrical discharge repeatedly occur between a work piece (2) and an electrode (1) for electrical discharge surface treatment, for which a compact formed by powder obtained by mixing 20 wt % or more of silicon with powder of a hard material or a solid body of silicon is used, so that the electrode material is moved to the work piece (2), including: a processing time decision step of observing an electrical discharge treatment surface formed on the work piece surface by the electrical discharge and deciding the electrical discharge surface treatment end time in a process where surface roughness formed by the electrical discharge on the electrical discharge treatment surface acquired from the observation result is increased and is then decreased.

Abstract: Using electrical discharge surface treatment of moving an electrode material to a work piece by repeatedly generating pulsed electrical discharge between an electrode for electrical discharge surface treatment (1) containing Si as a main component and a work piece (2) surface in order to form a surface layer excellent in an anti-corrosion property and an anti-erosion property which is useful in applications to anti-corrosion and anti-erosion parts, a surface layer formed with an amorphous structure, in which an Si component is contained in a range of 3 to 11 wt % and which has a thickness of 5 to 10 ?m, is formed on the work piece (2) surface.

Abstract: In order to establish an electric-discharge surface treatment capable of forming a smooth high-hardness coating, in the electric-discharge surface treatment in which pulsed electric discharge is generated between the electrode and a base material in a machining fluid or in the air by using a green compact, which is formed by compressing powder of an electrode material, as an electrode, and by using energy of the electric discharge, a coating including the electrode material or a reaction product of the electrode material reacted by the electric discharge energy is formed on a surface of the base material, wherein, as the powder of the electrode material, a mixed powder formed by mixing 10 to 75 vol % of Si powder to powder of a hard material is used.

Abstract: To form a coating film having an excellent wear-resistant property in a temperature range from low temperature to high temperature a coating-film forming method includes a metal-powder producing step of producing a metal powder containing an element exhibiting a lubricating property when oxidized; an oxidizing step of oxidizing the metal powder so that an amount of oxygen contained in the metal powder is within 6 weight % to 14 weight %; and a coating-film forming step of forming a coating film on a material subject to a treatment, the coating film having such a composition that an area where an oxygen content is 3 weight % or less and an area where an oxygen content is 8 weight % or more are distributed in a unit area of the coating film when the metal powder is in a melted state or a semi-melted state, and an oxygen content of the entire coating film after the metal powder is melted or semi-melted being within 5 weight % to 9 weight %.

Abstract: A method for forming a surface layer, the purpose thereof is to form a high erosion resistant film. The method for forming a surface layer includes: arranging a member (2) in a machining fluid (3); and forming the surface layer including silicon by spacing a silicon electrode (1) from the member (2) at a predetermined distance, and by supplying silicon component from the silicon electrode (1) to the member side by applying a predetermined voltage and generating electric discharge, and an iron-based metal texture including silicon of 3 to 11 wt % is formed at a thickness of 5 to 10 ?m at a portion to be treated by repetitively generating a electric discharge pulse in which a time integration value of a current value of the electric discharge pulse is in a range of 30 A·?s to 80 A·?s.

Abstract: An electrode for electrical-discharge surface treatment is made of a compact obtained by forming metal powder, metal compound powder, or conductive ceramics powder. Pulsed discharges between the electrode and a work in a working fluid or in air cause a film to form at the surface of the work, the film being made of a material of the electrode or made of a substance with which the material of the electrode reacts. A resistance of a surface of the electrode measured using a four-terminal method ranges from 5×10?3 ? to 10×10?3 ?, and an oxygen concentration in the electrode ranges from 4 weight % to 10 weight %.

Abstract: A method for forming a surface layer, the method including: arranging a member in a machining fluid; and forming a surface layer including silicon by supplying silicon component from the silicon electrode to the member side by applying a predetermined voltage and generating electric discharge, wherein a value of an electric discharge detection level is set to be equal to or larger than a value obtained by adding a voltage depression at the silicon electrode to an arc potential during electric discharge, and wherein the surface layer is formed on a surface of the member by repetitively performing, after the voltage is applied, detecting the electric discharge generated between the silicon electrode and the member by detecting a drop of the voltage to be lower than the electric discharge detection level, stopping applying the voltage for a predetermined time, and applying the voltage again after a predetermined break time.

Abstract: An electrical discharge surface treatment method for forming a coating film by generating a pulsed electrical discharge between an electrode and a workpiece in working fluid or gas using a green compact obtained by molding metal powder or metal alloy powder or a molded body obtained by heating the green compact as the electrode, and by melting an electrode material by an energy of the pulsed electrical discharge, forming a coating of the electrode material or a coating of a material obtained by a reaction of the electrode material by the energy of the pulsed electrical discharge on a surface of the workpiece, the electrical discharge surface treatment method includes generating the pulsed electrical discharge by mixing together two or more types of pulsed electrical discharges having different energies.

Abstract: To form a coating film having an excellent wear-resistant property in a temperature range from low temperature to high temperature a coating-film forming method includes a metal-powder producing step of producing a metal powder containing an element exhibiting a lubricating property when oxidized; an oxidizing step of oxidizing the metal powder so that an amount of oxygen contained in the metal powder is within 6 weight % to 14 weight %; and a coating-film forming step of forming a coating film on a material subject to a treatment, the coating film having such a composition that an area where an oxygen content is 3 weight % or less and an area where an oxygen content is 8 weight % or more are distributed in a unit area of the coating film when the metal powder is in a melted state or a semi-melted state, and an oxygen content of the entire coating film after the metal powder is melted or semi-melted being within 5 weight % to 9 weight %.

Abstract: A method of manufacturing an electrode for electrical-discharge surface treatment includes increasing oxygen content in the powder; mixing the powder, in which the oxygen content is increased, with an organic binder and a solvent to prepare a liquid mixture; granulating the powder in the liquid mixture to form granulated powder; and forming the granulated powder to prepare a compact in which an oxygen concentration ranges from 4 weight % to 16 weight %.