Unlock instant, AI-driven research and patent intelligence for your innovation.

Heat treatment process of vanadium boron microalloyed high strength steel

A technology of boron microalloying and high-strength steel, which is applied in the field of heat treatment of steel materials, can solve the problems of low yield strength, low fatigue life, and low strength, and achieve the effects of good ductility, increased strength, and excellent mechanical properties

Active Publication Date: 2015-09-16
INNER MONGOLIA BAOTOU STEEL UNION
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The sub-temperature quenching temperature is lower, but the sub-temperature quenching cannot obtain a higher yield strength, so the yield strength of the steel is relatively low, the strength is low, and the fatigue life is low

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
  • Heat treatment process of vanadium boron microalloyed high strength steel
  • Heat treatment process of vanadium boron microalloyed high strength steel
  • Heat treatment process of vanadium boron microalloyed high strength steel

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0027] Example 1 is a round steel bar of Φ18. The chemical composition mass percentage of the round steel bar is: C0.21%, Mn 1.35%, Si 0.45%, S 0.02%, P 0.015%, V0.07%, B 0.0018%, the balance is Fe and unavoidable of impurities. like image 3 As shown, it is the metallographic structure diagram of the hot-rolled round steel bar in Example 1 of the present invention. from image 3 It can be seen that the metallographic structure of the hot-rolled state is ferrite and pearlite.

[0028] The critical phase transition temperature of the steel in Example 1 was measured with a Formaster-F automatic phase changer, which were the temperature Ac1 at which austenite began to form when the steel was heated, and the temperature at which all ferrite was transformed into austenite when the hypoeutectoid steel was heated. Temperature Ac3, the temperature Ar1 at which austenite decomposes into ferrite and pearlite when the steel is cooled after high temperature austenitization, and the te...

Embodiment 2

[0034] Example 2 is a round steel bar of Φ25. The chemical composition mass percentage of the round steel bar is: C0.25%, Mn 1.50%, Si 0.45%, S 0.02%, P 0.015%, V0.09%, B 0.0025%, the balance is Fe and unavoidable of impurities. The specification of the round steel bar is larger than that of Example 1, and increasing the content of hardenability elements (C, V, Mn, B) is the design idea of ​​the chemical composition of the steel, and the metallographic structure of the hot-rolled state is ferrite body and pearlite.

[0035] The critical phase transition temperature of the steel of Example 2 was measured with a Formaster-F automatic phase changer, which were the temperature Ac1 at which austenite began to form when the steel was heated, and the temperature at which all ferrite was transformed into austenite when the hypoeutectoid steel was heated. Temperature Ac3, the temperature Ar1 at which austenite decomposes into ferrite and pearlite when the steel is cooled after high t...

Embodiment 3

[0041] Example 3 is a round steel bar of Φ25. The chemical composition mass percentage of the round steel bar is: C0.24%, Mn 1.7%, Si 0.8%, S 0.03%, P 0.03%, V0.1%, B 0.003%, the balance is Fe and unavoidable of impurities. The specification of the round steel bar is larger than that of Example 1, and increasing the content of hardenability elements (C, V, Mn, B) is the design idea of ​​the chemical composition of the steel, and the metallographic structure of the hot-rolled state is ferrite body and pearlite.

[0042] The critical phase transition temperature of the steel in Example 3 was measured with a Formaster-F automatic phase changer, which were the temperature Ac1 at which austenite began to form when the steel was heated, and the temperature at which all ferrite was transformed into austenite when the hypoeutectoid steel was heated. Temperature Ac3, the temperature Ar1 at which austenite decomposes into ferrite and pearlite when the steel is cooled after high temper...

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
tensile strengthaaaaaaaaaa
yield strengthaaaaaaaaaa
elongationaaaaaaaaaa
Login to View More

Abstract

The invention discloses a heat treatment process of a vanadium boron microalloyed high-strength steel. The process includes: pre-quenching, intercritical quenching and low temperature tempering. The obtained vanadium boron microalloyed high-strength steel comprises the following chemical components by mass: less than or equal to 0.25% of C, less than or equal to 1.7% of Mn, less than or equal to 0.8% of Si, less than or equal to 0.03% of S, less than or equal to 0.03% of P, less than or equal to 0.1% of V, 0.001%-0.003% of B, and the balance Fe and impurities. The vanadium boron microalloyed high-strength steel provided by the invention has excellent mechanical properties, and can be applied to panel products, building material products and special performance steel products. The heat treatment method involved in the invention substantially enhances the strength of the steel and endows the steel with good ductility.

Description

technical field [0001] The invention relates to the technical field of heat treatment of iron and steel materials, in particular to a heat treatment process of vanadium-boron microalloyed high-strength steel. Background technique [0002] In the production process of steel products, a certain heat treatment process is usually used to improve the properties of the steel. Sub-temperature quenching, also known as critical zone quenching, is to heat the hypoeutectoid structural steel with equilibrium or non-equilibrium original structure to the two-phase zone where ferrite and austenite coexist (that is, the critical zone temperature range), and the heat preservation is certain. time, and then the heat treatment process of quenching is carried out. Different from the conventional complete quenching process, the heating temperature of sub-temperature quenching is between the phase transition points Ac1 and Ac3, which is 50-100°C lower than that of conventional complete quenching...

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): C22C38/12C22C38/04C22C38/02C21D6/00C21D1/18
Inventor 冯岩青康利明
Owner INNER MONGOLIA BAOTOU STEEL UNION