A kind of free cutting stainless steel and preparation method thereof

A stainless steel, easy-cutting technology, applied in the field of metallurgy, can solve problems such as human hazards and environmental pollution, and achieve the effects of large cutting volume, high corrosion resistance and excellent cutting performance

Active Publication Date: 2019-08-30
太原钢铁(集团)有限公司
View PDF2 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the lead (Pb) element is a toxic and harmful element, which will pollute the environment in the process of smelting and production, and has potential harm to the human body in the process of product processing and use.

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 kind of free cutting stainless steel and preparation method thereof
  • A kind of free cutting stainless steel and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0091] In a second aspect, the present invention provides a method for preparing free-cutting stainless steel, comprising: (1) using blast furnace molten iron as a raw material to pretreat it; (2) continuously casting the pretreated molten iron into an ingot; (3) The ingot is heated and then rolled into the finished product.

[0092] In step (1), blast furnace molten iron is prepared by reacting iron ore and coke in a blast furnace.

[0093] In step (1), the pretreatment includes dephosphorization, desiliconization, and desulfurization of the blast furnace molten iron. Specifically, iron oxide balls and lime are added to molten iron to remove phosphorus, silicon and sulfur. P≤0.04, Si≤0.1%, and S≤0.02% in the stainless steel mother liquor after triple removal.

[0094] In step (2), before continuous casting, decarburization and denitrogenation roughing and LF furnace refining are performed on the pretreated molten iron, specifically, the molten iron is decarburized to 0.02-0....

Embodiment 1

[0101] The chemical composition of stainless steel is:

[0102] element symbol C Si mn P S Cr Mo Bi mass percentage 0.011 0.39 1.20 0.031 0.33 20.04 1.82 0.15 element symbol Pb Te Ni Cu V Nb N O mass percentage 0.01 0.027 0.2 0.1 0.1 0.03 0.02 0.016

[0103] Manufacturing method: After the molten steel has undergone three decarburization treatments, it is decarburized to 0.022% and nitrogen to 0.028% in the K-OBM-S furnace, and then undergoes deep decarburization to 0.008% and nitrogen to 0.020 in the VOD furnace, and is carried out in the LF furnace. The refining temperature is adjusted to 1585°C, and then the ladle is out of the station, and the molten steel is cast into ingots.

[0104] The temperature of the soaking section is 1120°C, and the holding time of the soaking section is calculated as 0.6min / mm; the heating rate of the heating section is 120°C / h; the temperature of the holding section is 1180°C...

Embodiment 2

[0110] The chemical composition of stainless steel is:

[0111] element symbol C Si mn P S Cr Mo Bi mass percentage 0.009 0.40 1.10 0.036 0.31 20.01 1.80 0.12 element symbol Pb Te Ni Cu V Nb N O mass percentage 0.05 0.025 0.23 0.11 0.09 0.03 0.022 0.017

[0112] Manufacturing method: After the molten steel has been subjected to three decarburization treatments, it is decarburized to 0.020% and nitrogen to 0.030% in the K-OBM-S furnace, and then goes through the VOD furnace for deep decarburization to 0.007%, and nitrogen to 0.024, and then goes through the LF furnace. The refining temperature is adjusted to 1590°C, and then the ladle is out of the station, and the molten steel is cast into ingots.

[0113] The temperature of the soaking section is 1150°C, and the holding time of the soaking section is calculated according to 0.8min / mm; the heating rate of the heating section is 150°C / h; the temperature of th...

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
tensile strengthaaaaaaaaaa
tensile strengthaaaaaaaaaa
Login to view more

Abstract

The invention provides free-cutting stainless steel which is prepared from the following components in percentage by weight: smaller than or equal to 0.014 percent of C, 0.36-0.60 percent of Si, 0.031-0.045 percent of P, 0.02-0.36 percent of S, 10.5-15 of S / Te, 0.95-1.21 percent of Mn, 19.7-20.3 percent of Cr, 1.7-2.0 percent of Mo, 0.001-0.1 percent of Pb, larger than or equal to 0.05 percent andsmaller than or equal to 0.25 percent of Bi+Pb, 0.016-0.03 percent of N, 0.21-0.3 percent of Ni, 0.1-0.17 percent of Cu, 0.09-0.15 percent of V, 0.026-0.05 percent of Nb, 0.016-0.02 percent of O andthe balance of Fe and inevitable impurities. The invention also provides a preparation method of the free-cutting stainless steel. The preparation method comprises the following steps of (1) by takingblast furnace molten iron as a raw material, performing pretreatment; (2) performing continuous casting on the molten iron subjected to pretreatment to prepare a cast ingot; and (3) heating the castingot, and then performing rolling to prepare a finished product.

Description

technical field [0001] The invention belongs to the field of metallurgy, and in particular relates to a free-cutting stainless steel and a preparation method thereof. Background technique [0002] In the field of metallurgical technology, in addition to the addition of sulfur (S) elements, the traditional ultra-free-cutting stainless steel also needs to add appropriate lead (Pb) elements to form S-Pb composite free-cutting effects with sulfur (S) elements, among which Sulfur (S) element and manganese (Mn) element form MnS, which is distributed in the matrix, and plays the role of splitting the matrix and breaking chips during the cutting process. In addition, due to the low melting point of the lead (Pb) element, it is easy to melt when heated during high-speed cutting, forming a liquid metal embrittlement effect. However, the lead (Pb) element is a toxic and harmful element, which will pollute the environment during the smelting and production process, and has potential ha...

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): C22C38/02C22C38/04C22C38/60C22C38/42C22C38/44C22C38/46C22C38/48C21D8/06
Inventor 车德会李建民王辉绵翟俊郎炜昀赵建伟
Owner 太原钢铁(集团)有限公司
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