Thermal treatment technology for improving low-temperature impact toughness of 25Cr2Ni4MoV steel forging

A technology for low temperature impact toughness and steel forgings, which is applied in the field of steel forging product production and can solve the problems of inability to meet usage requirements and poor impact toughness.

Active Publication Date: 2014-08-06
HENAN ZHONGYUAN SPECIAL STEEL EQUIP MFG CO LTD
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

After heat treatment of 25Cr2Ni4MoV steel forging products according to the conventional process, the strength can be guaranteed, but the low temperature impact toughness is poor, which cannot meet the use requirements

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Thermal treatment technology for improving low-temperature impact toughness of 25Cr2Ni4MoV steel forging
  • Thermal treatment technology for improving low-temperature impact toughness of 25Cr2Ni4MoV steel forging

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0018] Embodiment 1: The selected diameter is 440mm; the chemical composition is: C=0.22~0.30%, Si=0.15~0.30%, Mn≤0.50%, Ni=3.25~4.00%, Cr=1.40~2.00%, Mo=0.30~ 0.60%, V=0.05~0.15%, Cu≤0.20%, S≤0.015%, P≤0.015%; the steel type is 25Cr2Ni4MoV forgings. The heat treatment process is carried out by normalizing + quenching and tempering, such as figure 1 As shown, normalize first, preheat at 630°C for 2.5 hours, then raise the temperature to the normalizing temperature of 880°C, and the holding time is 1.2 hours / 100mm. After normalizing, four axial-flow blowers are placed on both sides of the upper and lower platforms respectively, and are sprayed directly onto the workpiece from multiple directions to force the workpiece to cool evenly and rapidly, so as to refine the grain and uniform structure and composition, and prepare for quenching. Prepare. After normalizing, adopt quenching and tempering treatment process, preheat at 630°C for 2.5 hours, then raise the temperature to que...

Embodiment 2

[0019] Embodiment 2: The selected diameter is 440mm; the chemical composition is: C=0.22~0.30%, Si=0.15~0.30%, Mn≤0.50%, Ni=3.25~4.00%, Cr=1.40~2.00%, Mo=0.30~ 0.60%, V=0.05~0.15%, Cu≤0.20%, S≤0.015%, P≤0.015%; the steel type is 25Cr2Ni4MoV forgings. The heat treatment process is carried out by normalizing + quenching and tempering, such as figure 1 As shown, normalize first, preheat at 650°C for 2 hours, then raise the temperature to the normalizing temperature of 890°C, and the holding time is 1.1 hours / 100mm. After normalizing, four axial-flow blowers are placed on both sides of the upper and lower platforms respectively, and are sprayed directly onto the workpiece from multiple directions to force the workpiece to cool evenly and rapidly, so as to refine the grain and uniform structure and composition, and prepare for quenching. Prepare. After normalizing, adopt quenching and tempering treatment process, preheat at 650°C for 2 hours, then raise the temperature to quenchi...

Embodiment 3

[0020] Embodiment 3: The selected diameter is 440mm; the chemical composition is: C=0.22~0.30%, Si=0.15~0.30%, Mn≤0.50%, Ni=3.25~4.00%, Cr=1.40~2.00%, Mo=0.30~ 0.60%, V=0.05~0.15%, Cu≤0.20%, S≤0.015%, P≤0.015%; the steel type is 25Cr2Ni4MoV forgings. The heat treatment process is carried out by normalizing + quenching and tempering, such as figure 1 As shown, normalize first, preheat at 670°C for 1.5 hours, then raise the temperature to the normalizing temperature of 900°C, and the holding time is 1 hour / 100mm. After normalizing, four axial-flow blowers are placed on both sides of the upper and lower platforms respectively, and are sprayed directly onto the workpiece from multiple directions to force the workpiece to cool evenly and rapidly, so as to refine the grain and uniform structure and composition, and prepare for quenching. Prepare. After normalizing, adopt quenching and tempering treatment process, preheat at 670°C for 1.5 hours, then raise the temperature to quench...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
diameteraaaaaaaaaa
Login to view more

Abstract

The invention belongs to the technical field of production of steel forgings used at low temperatures, and in particular relates to a heat treatment technology requiring high low-temperature impact toughness, in particular to a heat treatment process for improving the low-temperature impact toughness of 25Cr2Ni4MoV steel forgings, ① normalizing heating, ② Normalizing cooling, ③ quenching heating, ④ quenching cooling, while ensuring the strength of the material, it can effectively improve the low temperature impact toughness and prolong the service life of the product.

Description

technical field [0001] The invention belongs to the technical field of production of steel forgings used at low temperatures, and in particular relates to a heat treatment technology requiring high low-temperature impact toughness, in particular to a heat treatment process for improving the low-temperature impact toughness of 25Cr2Ni4MoV steel forgings. Background technique [0002] For steel forging products used at low temperature, due to the low temperature of the working environment, the brittleness of the product material will increase during long-term use. If the original steel forging material has high strength and poor low temperature impact toughness, it will be in a very short Failure forms such as fracture occur due to excessive brittleness within a certain period of time, reducing the service life. In order to make this type of product work normally and avoid early failure, it must have high hardness and good low-temperature impact toughness under use. After hea...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): C21D8/00C21D6/00C21D1/28C21D1/18
Inventor 赵颖赵玉李亚平
Owner HENAN ZHONGYUAN SPECIAL STEEL EQUIP MFG CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products