A phase ratio control method of two-phase corrosion-resistant layer on carbon steel surface

A surface surfacing and corrosion-resistant layer technology, applied in the direction of manufacturing tools, welding equipment, arc welding equipment, etc., can solve the problems of tissue transformation dynamics deviating from the equilibrium state, difficult to obtain, etc., to improve surfacing efficiency, good forming, Excellent forming effect

Active Publication Date: 2021-07-20
NANJING INST OF TECH
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

According to the Cr-Ni binary phase diagram, when the contents of Cr and Ni are 22% and 5% respectively, an approximately equal proportion austenite + ferrite duplex structure can be formed in an equilibrium state, but the actual surfacing process Heating is a non-equilibrium thermal process, and its microstructure transformation kinetics is far away from the equilibrium state, so it is often difficult to obtain an equal proportion of austenite + ferrite duplex structure

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 phase ratio control method of two-phase corrosion-resistant layer on carbon steel surface
  • A phase ratio control method of two-phase corrosion-resistant layer on carbon steel surface

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0034]Before surfacing operation, degrease and derust the base metal, and preheat the base metal to 100°C; then surfacing the transition isolation layer, filling layer and cover layer on the base metal in sequence. Electrode arc welding with a diameter of 4.0mm and a model of E309LMo is used to form a transition isolation layer; a diameter of 4.0mm and a model of E2594 is used for arc welding to form a filling layer; before welding, the electrode is heat-preserved and dried at 200°C 2 hours. For SMAW (stick arc welding), the welding current is 140A, the arc voltage is 22V, and the welding speed is 250mm / min. Finally, argon tungsten arc welding with a diameter of 2.4mm and a model of ER2594 is used to form a cover layer; GTAW (argon tungsten arc welding) selects a welding current of 110A, an arc voltage of 12V, and a welding speed of 160mm / min.

[0035] During the surfacing welding process, the interlayer temperature is controlled to 120°C after one surfacing welding is comple...

Embodiment 2

[0037] Before surfacing operation, degrease and derust the base metal, and preheat the base metal to 100°C; then surfacing the transition isolation layer, filling layer and cover layer on the base metal in sequence. Electrode arc welding with a diameter of 4.0mm and a model of E309LMo is used to form a transition isolation layer; a diameter of 4.0mm and a model of E2594 is used for arc welding to form a filling layer; before welding, the electrode is heat-preserved and dried at 200°C 2 hours. For SMAW (stick arc welding), the welding current is 150A, the arc voltage is 25V, and the welding speed is 250mm / min. Finally, argon tungsten arc welding with a diameter of 2.4mm and a model of ER2594 is used to form a cover layer; GTAW (argon tungsten arc welding) selects a welding current of 120A, an arc voltage of 15V, and a welding speed of 160mm / min.

[0038] During the surfacing welding process, the interlayer temperature is controlled to 120°C after one surfacing welding is compl...

Embodiment 3

[0040] Before surfacing operation, degrease and derust the base metal, and preheat the base metal to 100°C; then surfacing the transition isolation layer, filling layer and cover layer on the base metal in sequence. Electrode arc welding with a diameter of 4.0mm and a model of E309LMo is used to form a transition isolation layer; a diameter of 4.0mm and a model of E2594 is used for arc welding to form a filling layer; before welding, the electrode is heat-preserved and dried at 200°C 2 hours. For SMAW (stick arc welding), the selected welding current is 150A, the arc voltage is 26V, and the surfacing welding speed is 250mm / min. Finally, argon tungsten arc welding with a diameter of 2.4mm and a model of ER2594 is used to form a cover layer; GTAW (argon tungsten arc welding) selects a welding current of 120A, an arc voltage of 16V, and a welding speed of 160mm / min.

[0041] During the surfacing welding process, the interlayer temperature is controlled to 120°C after one surfaci...

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
diameteraaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for controlling the phase proportion of a two-phase corrosion-resistant layer on the surface of carbon steel. Austenitic deposited metal is used as a transitional isolation layer; high-current and high-efficiency arc surfacing welding is performed with high-chromium and high-nickel stainless steel electrodes to form a filling layer, that is, corrosion-resistant surfacing welding of superalloyed austenite-ferrite dual-phase structure During the surfacing process, the interlayer temperature is controlled below 120°C; the cover surface is surfacing with low-current argon tungsten arc welding to form a cover layer; after the surfacing welding is completed, post-weld heat treatment is not required; 24 hours after welding Conduct penetrant flaw detection, and use a ferrite tester to measure the ferrite content. The welding method provided by the invention can form an approximately equal-proportion dual-phase corrosion-resistant surfacing layer, and does not require heat treatment after welding, which can simplify the processing technology and reduce the manufacturing cost.

Description

technical field [0001] The invention relates to a method for controlling the phase proportion of a two-phase corrosion-resistant layer for overlay welding on a carbon steel surface, and belongs to the technical field of welding processing of chemical equipment. Background technique [0002] Duplex stainless steel composed of austenite and ferrite has more beneficial corrosion resistance than single-phase austenitic stainless steel, and its structure has an equal proportion of ferrite + austenite duplex structure, so it has both characteristics of phase organization. Due to the existence of ferrite, the yield strength of duplex stainless steel is about twice that of ordinary austenitic stainless steel, and the existence of austenite ensures its good plasticity and toughness. In terms of stress corrosion resistance, duplex stainless steel has a significant advantage over austenitic stainless steel. In the manufacture of chemical equipment, the surface of cost-effective carbo...

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): B23K9/04B23K9/167B23K9/235
CPCB23K9/042B23K9/167B23K9/235
Inventor 李晓泉陈一鑫云叶菱郝本行成家林
Owner NANJING INST OF TECH
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