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

Method for controlling boron content of boron-containing steel smelted by vacuum induction furnace

A technology of vacuum induction furnace and boron content, which is applied in the field of vacuum induction furnace smelting boron-containing steel to control boron content, and can solve problems such as difficult to meet the precise control of boron in steel types

Active Publication Date: 2013-06-12
SHANXI TAIGANG STAINLESS STEEL CO LTD
View PDF3 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The existing method for smelting boron-containing steels in vacuum induction furnaces to control boron content is to add boron to increase boron in the later stage of smelting. Because boron reacts with oxygen in molten steel, the boron recovery rate is below 80%, and because crucible refractory materials contain sticky Binder boric acid (H 3 BO 3 ), decomposed in the process of steelmaking, resulting in the increase of boron in molten steel, and the amount of boron increase is between 0.001-0.003%.
Therefore, the fluctuation range of boron is generally 0.005%, which is difficult to meet the precise control of boron content in steel

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
  • Method for controlling boron content of boron-containing steel smelted by vacuum induction furnace
  • Method for controlling boron content of boron-containing steel smelted by vacuum induction furnace
  • Method for controlling boron content of boron-containing steel smelted by vacuum induction furnace

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0032] The equipment adopts a 200kg high vacuum induction furnace: the ultimate vacuum is 6.67×10 -2 Pa, the power supply is 250KW, the frequency is 2500HZ, and the furnace load is 100kg. Steel Type: Welding Wire Steel EQ316L

[0033] The present invention smelting one batch of EQ316L steel needs scrap steel, alloy and ferroboron weight to see Table 1, and the standard composition and control target of EQ316L composition are shown in Table 2.

[0034] Table 1

[0035] Raw material type

[0036] Table 2

[0037]

[0038] This embodiment is the following steps in sequence:

[0039] I prepare the crucible

[0040] The used crucible is a crucible knotted with fused magnesia, and the weight ratio of boric acid in the material of the knotted crucible is 0.8%. After the crucible is sintered, five heats of steel are smelted.

[0041] II prepare raw materials

[0042] Put 0.030kg ferroboron and 0.05kg aluminum shot into the hopper.

[0043] III charging

[0044] Pu...

Embodiment 2

[0064] The equipment adopts a 200kg high vacuum induction furnace: the ultimate vacuum is 6.67×10 -2 Pa, the power supply is 250KW, the frequency is 2500HZ, and the furnace load is 100kg. Steel Type: Stainless Steel UNS N08926

[0065] See Table 4 for the weight (kg) of pure iron, alloy and ferroboron needed to smelt a furnace of UNS N08926 steel in the present invention, and see Table 5 for the standard composition and control objectives of UNS N08926.

[0066] Table 4

[0067] Raw material type

pure iron

Chromium nitride

manganese nitride

metal chrome

nickel beans

Ferromolybdenum

special silicon

Electrolytic copper

Ferroboron

Aluminum shot

Amount added

41.0

1.8

1.4

19.8

25.3

10.5

0.24

1.05

0.019

0.05

[0068] table 5

[0069]

[0070] This embodiment is the following steps in sequence:

[0071] I prepare the crucible

[0072] The used crucible is a...

Embodiment 3

[0099] The equipment adopts a 200kg high vacuum induction furnace: the ultimate vacuum is 6.67×10 -2 Pa, the power supply is 250KW, the frequency is 2500HZ, and the furnace load is 100kg. Steel Type: Oriented Silicon Steel N1

[0100] The weights of pure iron, alloy and ferroboron needed to smelt a furnace of oriented silicon steel N1 in the present invention are shown in Table 7, and the standard composition and control target of N1 are shown in Table 8.

[0101] Table 7

[0102]

[0103] Table 8

[0104]

[0105] This embodiment is the following steps in sequence:

[0106] I prepare the crucible

[0107] The used crucible is a crucible knotted with fused magnesia, the weight proportion of boric acid in the material of the knotted crucible is 0.8%, and the crucible is sintered and smelted through 8 heats of steel.

[0108] II prepare raw materials

[0109] Put 0.030kg ferroboron and 0.05kg aluminum shot into the hopper.

[0110] III charge

[0111] Put the pure ...

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

No PUM Login to View More

Abstract

The invention relates to a method for controlling the boron content of boron-containing steel smelted by a vacuum induction furnace, which includes the steps: I preparing a crucible for smelting steel not less than the quantity of steel in 5 furnaces, II preparing raw materials and placing iron boron and aluminum pills into an alloy hopper, III charging pure iron or scrap steel and iron alloy or return scrap into the crucible and charging silicon iron, manganese metal and iron boron into the hopper, IV closing a furnace cover, vacuumizing to enable the pressure in the furnace not more than 10Pa and heating the furnace charge by means of power supply, V smelting the furnace charge with the smelting speed not more than one half of the maximum capacity of one furnace per hour, VI turning into high-vacuum refining for 18-22 minutes when the raw materials are smelted into molten steel and the pressure in the furnace is not more than 2.0 Pa, VII filling argon into the furnace after vacuumizing stops, VIII alloying by regulating other components under protection of the argon, IX performing final deoxidization, and X adding iron boron for smelting. By the aid of the method, the boron quantity increase is not more than 0.0005%, and fluctuation of boron in the steel is not more than + / -0.001%.

Description

technical field [0001] The invention relates to a method for controlling boron content in smelting boron-containing steel in a vacuum induction furnace. Background technique [0002] Boron is a trace alloying element in steel or alloy, which plays an important role in improving the strength and hardenability of steel. Boron is a relatively active element. Boron is easily oxidized at steelmaking temperature. The existing method for smelting boron-containing steels in vacuum induction furnaces to control boron content is to add boron to increase boron in the later stage of smelting. Because boron reacts with oxygen in molten steel, the boron recovery rate is below 80%, and because crucible refractory materials contain sticky Binder boric acid (H 3 BO 3 ), decomposed in the process of steelmaking, resulting in the increase of boron in molten steel, and the amount of boron increase is between 0.001-0.003%. Therefore, the fluctuation range of boron is generally 0.005%, which i...

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): C21C7/10C22C38/58C22C33/06
Inventor 赵鸿燕王贺利方旭东
Owner SHANXI TAIGANG STAINLESS STEEL CO LTD