A heat treatment method for preventing abnormal grain growth of heat-resistant alloy thick-walled tubes

A technology of abnormal grain growth and heat treatment method, which is applied in the field of heat treatment to prevent abnormal grain growth of heat-resistant alloy thick-walled tube, can solve the problem of few reports on heat treatment, and achieve the improvement of radial temperature field, radial structure and heat treatment. Good uniformity of properties and the effect of improving yield

Active Publication Date: 2020-11-13
CENT IRON & STEEL RES INST
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] Since the whole-process preparation technology of heat-resistant alloys belongs to a high-tech and high-value-added product in the special steel field of a country, there are few domestic and foreign reports on heat treatment of similar alloys and product types

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
  • A heat treatment method for preventing abnormal grain growth of heat-resistant alloy thick-walled tubes
  • A heat treatment method for preventing abnormal grain growth of heat-resistant alloy thick-walled tubes
  • A heat treatment method for preventing abnormal grain growth of heat-resistant alloy thick-walled tubes

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0022] Example of the present invention C-HRA- The main components of the heat-resistant alloy are (wt.%): Cr 22.0%; C0.06%; Mn 0.3%; Co 12.0%; Mo 8.8%; Ti 0.5%; Al 1.0%; W 0.1%; B 0.0035% ; Zr0.03%; Nb 0.1%; P 0.006%; S 0.001%; ​​Mg 0.005; Nickel is the balance and an inevitable impurity element.

[0023] The invention smelts 2 6-ton alloy ingots according to the above-mentioned composition VIM+ESR process, and uses a vertical hot extruder to extrude the pipes. The product specifications are large-diameter thick-walled heat-resistant steel pipes with an outer diameter of Φ559mm × a wall thickness of 120mm. One is implemented according to the existing technology; the other is implemented according to the process of the present invention.

[0024] The existing technology is implemented as follows: the furnace is installed at a temperature of 300°C, heated to 1170°C at a rate of 70-100°C / h after the pass-through insulation, and kept for 1 hour after the pass-through insulation, and ...

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
crystal sizeaaaaaaaaaa
Login to view more

Abstract

The invention discloses a heat treatment method for preventing the abnormal growth of heat-resistant alloy thick-walled pipe grains, and belongs to the technical field of heat treatment of heat-resistant alloy steel pipes. The heat treatment method comprises the steps that pierced billets which are extruded by a vertical extruder are adopted, the wall thickness is 70-120mm, charging is carried outat 400 DEG C, the temperature is raised to 800-820 DEG C at a heating rate of 60 DEG C / h, and the temperature is kept for 2-4 hours; the temperature is raised to 970-990 DEG C at a heating rate of 80DEG C / h, and the temperature is kept for 1-3 hours; then the temperature is raised to 1090-1120 DEG C at a heating rate of 100 DEG C / h, and the temperature is kept for 1-6 hours; and finally the temperature is raised to 1150-1160 DEG C at a temperature rate of 100 DEG C / h, the temperature is kept for 1-7 hours, and water quenching is carried out to room temperature after discharging. The heat treatment method has the advantage that the abnormal growth of austenite grains is prevented, radial temperature fields of thick-walled pipes are improved, the grains are uniform, the level differences are small, and the uniformity of the radial structure and performance of the thick-walled pipes are greatly improved.

Description

Technical field [0001] The invention belongs to the field of heat treatment of heat-resistant alloy steel pipes, and in particular provides a heat treatment method for preventing abnormal growth of heat-resistant alloy thick-walled pipe grains, namely: preventing heat-resistant alloy thick-walled pipes (70-120mm) from abnormally growing grains Large heat treatment method prevents abnormal growth of nickel-based alloy thick wall (70~120mm) crystal grains, resulting in the mixed crystal of the finished tube or the actual grain size of the product exceeding the standard requirements, especially suitable for 700℃ steam parameters exceeding (super) critical thermal power Manufacture of related pipelines for units. Background technique [0002] Increasing the steam parameters (temperature and pressure) of thermal power units is the most important way to improve the thermal efficiency of power generation and to achieve coal saving and emission reduction. However, the main "bottleneck" ...

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): C22F1/10C22C19/05
CPCC22C19/055C22F1/002C22F1/10
Inventor 陈正宗刘正东包汉生董陈郑佳壮杨钢
Owner CENT IRON & STEEL RES INST
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap