47results about How to "Shorten heat treatment cycle" patented technology

The invention provides a hardening method of a steel member in which a heat cycle time required for a sequence of hardening process can be shortened and heat treatment deformation after hardening is small. Provided is a hardening method of a steel member in which coating treatment in which one part or the whole of a surface of a steel member before being heated to a hardening temperature is coated with graphite, then the steel member after the coating treatment is heated to a hardening temperature in a heating furnace having an exothermic body, and cooled. In heating to the hardening temperature, at least one time in the heating is preferably performed in a vacuum or a decompressed atmosphere. The coating treatment can be performed with a carburization inhibitor or a decarbonization inhibitor which is coated on a surface of the steel member.

The invention relates to a martensite tissue ultra-refining method of steel for a die-casting die. The method comprises the steps that (1) an ultra-refined forging is subjected to vacuum heat treatment and heat preservation, then is subjected to gas quenching, so that the temperature of the surface of the forging is reduced to 255-275 DEG C, the forging is kept at the temperature for 105-130 s, and thus the temperature difference between the surface and the core part of the forging is controlled to be 50-80 DEG C; (2) heat preservation is carried out under the protection atmosphere condition of 360-400 DEG C; (3) heat preservation is carried out at the temperature of 550-600 DEG C, and then the forging is subjected to oil quenching to room temperature; and (4) 1-3 times of de-stress tempering treatments are carried out till the hardness meets the requirements. The method is simple, easy to operate, and is particularly suitable for large-specification die steel; and the heat treatment period is shortened, the impact toughness is improved by 12%-20% under the conventional die casting requirement hardness condition, the service life of the die-casting die can be prolonged, and the hardness requirement of the high-performance die-casting die steel for aluminum alloy automobile part die-casting is met.

The invention relates to a preparation method for a wear resistant metal pipeline with an internal anticorrosive coating. The preparation method comprises the following steps: obtaining a wear resistant pipeline body through centrifugal casting; allowing the wear resistant pipeline body to be subjected to quenching, high temperature tempering, solution strengthening heat treating, and two-time tempering and dispersion hardening heat processing; and finally spraying the anticorrosive coating on an internal wall of the pipeline through air. According to the preparation method, the metal pipeline has higher hardness and wear-resisting property; and the anticorrosive coating has excellent waterproof and antifouling effect, and high temperature resisting property.

The invention relates to an anti-corrosion, high-temperature-resisting and wear-resisting cast pipe. A wear-resisting pipeline body is manufactured by means of centrifugal casting; after the steps of quenching, high-temperature tempering, solid solution strengthening heat treatment and two times of tempering dispersion hardening heat treatment, the inner wall of the pipeline body is coated with a water glass nanometer composite coating configured by a test; and then, the coating is cooled after being cured at a high temperature, so that a high-temperature-oxidation resisting anti-corrosion coating inner layer is obtained. The manufactured metal pipeline has high hardness and high wear-resisting performance. The anti-corrosion coating has excellent water-resisting performance, an excellent antifouling effect and good high-temperature-resisting performance.

The invention relates to a heat treatment method of alloy steel after forging. The method comprises the steps of forming a decarburization-preventing and oxidation-resistant protective layer on a surface of an alloy steel workpiece; and then carrying out isothermal annealing on a to-be-treated alloy steel workpiece with the decarburization-preventing and oxidation-resistant protective layer. The heat treatment method of the alloy steel after forging can effectively prevent the surface of the to-be-treated alloy steel workpiece from decarburization and oxidation and shorten a heating period, thereby being beneficial to improve comprehensive mechanical performance of the to-be-treated alloy steel workpiece.

The invention provides a heat processing apparatus used for the heat treatment of a workpiece, wherein the rod shaft part of the upper portion of a workpiece or the cup-shaped body of the lower portion of the workpiece is subjected to heat treatment by the heat processing apparatus. The heat processing apparatus comprises a temporary phase determination mechanism, a formal phase determination mechanism, a workpiece lower portion heat treatment part and a workpiece upper portion heat treatment part. The heat processing apparatus also comprises one ore more than two of the following members: a desk type conveying mechanism and a suspension bracket type conveying mechanism used for confirming the position of a workpiece or a centering abutting member; a processing component symmetrically equipped with rotary clamping mechanisms with respect to a rotary shaft; a heat treatment head for fixing a fixed base at a predetermined position and connected with a workpiece cooling water pathway; a heating coil for connecting a powered terminal and a power supply terminal and connected with the workpiece cooling water pathway; a workpiece upper portion heating unit for fixing the heating coil of the rod shaft part and the heating coil of the cylinder shaft part at different layers; a rotary cooling device for cooling a workpiece during rotation; and a locking construction for preventing the driving of a heat treatment production line when the locking of an open-close door is unlocked.

The invention relates to an as-forged rapid hydrogen diffusion treatment method for a nitrogen alloying anti-corrosion die steel, which comprises the following steps of: after forging the nitrogen alloying anti-corrosion die steel, heating to the temperature of 690 to 710 DEG C and carrying out heat preservation according to the heat preservation time of 5 to 6 hours per 100mm of the nitrogen alloying anti-corrosion die steel; heating to 820 to 840 DEG C in an austenite region in 1 to 2 hours and carrying out heat preservation; cooling to the temperature of 690 to 710 DEG C in 2 to 3 hours and carrying out heat preservation according to the heat preservation time of 3 to 4 hours per 100mm of the nitrogen alloying anti-corrosion die steel; and then cooling to the temperature of below 250 DEG C. According to the invention, by a method of circularly heating up and down near a phase transformation point, the tissues of the nitrogen alloying anti-corrosion die steel are transformed repeatedly from austenite to pearlite and the diffusion of hydrogen in the steel is quickened by utilizing the change of the solubility of the hydrogen in different tissues, so that the as-forged hydrogen diffusion treatment time of the nitrogen alloying anti-corrosion die steel is shortened.