CN117123727A - Forging method for refining grains of high-temperature alloy thin-wall ring-like piece - Google Patents

Abstract

The invention discloses a forging method for grain refinement of high-temperature alloy thin-walled ring parts, which is characterized by the steps of primary ring blank forming, rolling and expanding ring part forming and heat treatment, wherein the rolling and expanding ring part forming steps are: After the primary ring blank is heated to a forging temperature of 1080°C-1110°C in an electric furnace, it is put into a ring rolling mill and rolled into shape. During the rolling process, end rolling equipment is used, and the deformation amount is 27% to 42%. Ring forgings. The end-rolling equipment adds the use of tapered roller equipment during the hole expansion process to control the growth of the height-direction dimension of the ring, so that the height-direction dimension of the ring is within the allowable tolerance range of the forging. This method can make the structure and properties uniform, and is suitable for the forging of high-temperature alloy thin-walled rings.

Description

Forging method for grain refinement of high-temperature alloy thin-walled rings

Technical field

The invention relates to a forging method, in particular to a forging method for refining the grains of high-temperature alloy thin-walled rings.

Background technique

GH4099 is a highly alloyed nickel-based aging plate alloy that is comprehensively strengthened with cobalt, tungsten, molybdenum, aluminum, and titanium elements to give the alloy high thermal strength. It can be used for a long time below 900°C, and the maximum working temperature can reaches 1000℃. The alloy has a stable structure and satisfactory cold and hot processing forming and welding process properties, so it is widely used in large plate structural parts.

GH4099 can usually be used directly after solution treatment without aging treatment. The control of the forging heating and forming process is the difficulty in forging this material, which has an important impact on the internal structure and performance. The grain size of the forging will also have an impact on the welding performance of the material. Therefore, controlling the grain size level of the forging can effectively reduce the tendency of cracks on the material surface during the welding process.

The GH4099 high-temperature alloy is heated to 1140°C in a natural gas furnace and produced with a free forging hammer to obtain a preform. After cooling and checking the surface quality of the forging, it is heated to 1140°C and rolled on a hole expansion machine to obtain a ring product. The physical and chemical properties are tested and the data is in the standard Within the range, but the margin is not large. Check the grain size of the forging and the result is level 2-3. The grain structure is too large, which has a certain impact on the performance of the forging. The microstructure of forgings is sensitive to the influence of temperature, and the uniformity of the structure can also be achieved by controlling the forging heating temperature and holding time and increasing the amount of forging deformation.

Lowering the forging heating temperature can effectively reduce the growth rate of the internal structure of the billet during the heating and insulation process. However, lowering the temperature will increase the tendency of forging cracks. While ensuring that the damage is small, lowering the forging temperature can reduce the grain size after forging. The degree level reaches level 4.5 or above. Therefore, accurately controlling the forging temperature and process and obtaining the expected structure are key issues in the forging of GH4099 high-temperature alloy ring-rolled forgings.

Contents of the invention

The technical problem to be solved by this invention is to improve the deformation performance of forgings under the action of multi-directional compressive stress of GH4099 high-temperature alloy material, avoid forging cracks due to low temperature and multi-directional stress, and obtain a stable and uniform forging structure. Expansion method. It can obtain stable physical and chemical properties while improving the structural reliability of GH4099 high-temperature alloy components.

In order to solve the above technical problems, the present invention adopts the following technical solutions to achieve:

The GH4099 bar cut out of the specifications is heated to a forging temperature of 1100°C-1140°C. It is upsetting, punched, and machined on the free forging hammer to remove the inner hole burrs and defects, and then the preform is placed on the horse rack. On the equipment, the inner hole size is enlarged by a free forging hammer to obtain a primary ring blank;

After the primary ring blank is heated to a forging temperature of 1080°C-1110°C in an electric furnace, it is put into a ring rolling mill and rolled into shape. End rolling technology is used during the rolling process, and the deformation amount is 27% to 42%. , obtain ring forgings. The end rolling technology is to use a tapered roller to control the growth of the height direction of the ring during the hole expansion process, so that the height direction of the ring is within the allowable tolerance range of the forging;

The GH4099 ring forging is subjected to solution heat treatment. The solid solution is to heat the GH4099 ring forging to 1080°C to 1100°C, then water-cool it for 30 minutes, take it out, and then air-cool it to room temperature.

Compared with the prior art, the beneficial effects of the present invention are as follows:

The forging method for grain refinement of high-temperature alloy thin-walled ring parts of the present invention, and the rolling forming method of GH4099 high-temperature alloy thin-walled ring forgings, by adjusting the forging heating temperature, the initial forging temperature of the forging blank, and the final forging By controlling the temperature and forging deformation, high-temperature alloy ring forgings with excellent thin-walled structural properties can be obtained.

Detailed ways

To implement the forging method for grain refinement of high-temperature alloy thin-walled rings according to the present invention, it is necessary to provide equipment such as a forging heating furnace, a press, and a manipulator. Specific implementation of this method:

The GH4099 bar cut out of the specifications is heated to a forging temperature of 1100°C-1140°C. It is upsetting, punched, and machined on the free forging hammer to remove the inner hole burrs and defects, and then the preform is placed on the horse rack. On the equipment, the inner hole size is enlarged by a free forging hammer to obtain a primary ring blank;

After the primary ring blank is heated to a forging temperature of 1080°C-1110°C in an electric furnace, it is put into a ring rolling mill and rolled into shape. End rolling technology is used during the rolling process, and the deformation amount is 27% to 42%. , obtain ring forgings. The end rolling technology is to use a tapered roller to control the growth of the height direction of the ring during the hole expansion process, so that the height direction of the ring is within the allowable tolerance range of the forging;

The GH4099 ring forging is subjected to solution heat treatment. The solid solution is to heat the GH4099 ring forging to 1080°C to 1100°C, then water-cool it for 30 minutes, take it out, and then air-cool it to room temperature.

Claims (1)

1. A forging method for grain refinement of high-temperature alloy thin-walled rings, which is characterized by including the following steps: The GH4099 bar cut out of the specifications is heated to a forging temperature of 1100°C-1140°C. It is upsetting, punched, and machined on the free forging hammer to remove the inner hole burrs and defects, and then the preform is placed on the horse rack. On the equipment, the inner hole size is enlarged by a free forging hammer to obtain a primary ring blank; After the primary ring blank is heated to a forging temperature of 1080°C-1110°C in an electric furnace, it is put into a ring rolling mill and rolled into shape. End rolling technology is used during the rolling process, and the deformation amount is 27% to 42%. , obtain ring forgings. The end rolling technology is to use a tapered roller to control the growth of the height direction of the ring during the hole expansion process, so that the height direction of the ring is within the allowable tolerance range of the forging; The GH4099 ring forging is subjected to solution heat treatment. The solid solution is to heat the GH4099 ring forging to 1080°C to 1100°C, then water-cool it for 30 minutes, take it out, and then air-cool it to room temperature.