CN102691000A

CN102691000A - Steel plate for engineering machinery and rolling and heat treatment technologies thereof

Info

Publication number: CN102691000A
Application number: CN2012101999790A
Authority: CN
Inventors: 董瑞峰; 闫波; 温利军; 吴鹏飞; 高志国; 李文艺; 刘哲; 张军; 丁晓志; 张大治; 李�浩
Original assignee: Baotou Iron and Steel Group Co Ltd
Current assignee: Baotou Iron and Steel Group Co Ltd; Inner Mongolia Baotou Steel Union Co Ltd
Priority date: 2012-06-18
Filing date: 2012-06-18
Publication date: 2012-09-26

Abstract

The invention discloses a steel plate for engineering machinery and rolling and heat treatment technologies thereof, belonging to the field of material forming technology. The plate blank comprises the following chemical components in percentage by weight: 0.05-0.12% of C, 0.15-0.50% of Si, 1.5-1.9% of Mn, less than or equal to 0.018% of P, less than or equal to 0.005% of S, greater than or equal to 0.020% of Alt, 0.030-0.060% of Nb, 0.030-0.065% of V, 0.008-0.020% of Ti, 0.150-0.30% of Cr, 0.08-0.20% of Mo, less than or equal to 0.0010% of RE, and the balance of Fe and inevitable impurities. In the rolling technology, the heating temperature is 1,200-1,250 DEG C, the heating time is longer than or equal to 200 minutes, the soaking time is longer than or equal to 30 minutes, the rough rolling start temperature is 1,180-1,230 DEG C, the finish rolling start temperature is 870-920 DEG C, the finishing temperature is 850-890 DEG C, the Acc final cooling temperature is 520-620 DEG C, and the cooling speed is 10-20 DEG C/s. In the heat treatment technology, the tempering temperature is 600-690 DEG C, and a steel plate with the thickness of 60-100mm is produced. In terms of mechanical properties, the tensile strength is greater than or equal to 690MPa, the yield strength is greater than or equal to 550MPa, the elongation is greater than or equal to 18%, the longitudinal impact energy at (-20)-(-40) DEG C is greater than 120J, the Z-direction property is greater than 40%, and the carbon equivalent is not greater than 0.47%; and moreover, the welding property is good, and the production cost is low.

Description

A kind of engineering machinery is with steel plate and rolling, thermal treatment process thereof

Technical field

A kind of engineering machinery belongs to the forming materials technical field with steel plate and rolling, thermal treatment process thereof, particularly hot-rolled steel plate and thermal treatment process.

Background technology

At present; Engineering machinery is comparatively common with quenched and tempered steel with steel plate, is that 200810041043 " 700MPa grade high strength and high toughness hardened and tempered steel plate and method of manufacture thereof cheaply ", number of patent application are that 200810042124 " good extra-thick quenched and tempered steel plate and the method for manufacture thereof of a kind of obdurability coupling ", number of patent application are 201110337489.8 " a kind of engineering machinery is with high-performance hardened and tempered steel plate and production technique thereof " etc. like number of patent application.With regard to the composition System Design, be main with low-carbon low-alloy steel mostly.This patent is in order to practice thrift the production technique cost; Develop the low-cost engineering machinery of a kind of thick specification and use steel plate, handle, can obtain ys >=550MPa, tensile strength >=690MPa through the TMCP+ tempering process; The impact of collision merit is greater than 120J under-20 ℃～-40 ℃ conditions, Z to performance greater than 40%.Carbon equivalent is not more than 0.47%, and welding property is good, and production cost is low.

Summary of the invention

The objective of the invention is to disclose a kind of engineering machinery with steel plate and rolling, thermal treatment process thereof, the chemical ingredients of its slab and content (weight percent) should meet: C 0.05-0.12%, Si 0.15-0.50%, Mn 1.5-1.9%; P≤0.018%, S≤0.005%, Alt>=0.020%, Nb 0.030-0.060%; V 0.030-0.065%, Ti 0.008-0.020%, Cr 0.150-0.30%; Mo 0.08-0.20%, RE≤0.0010%, surplus is Fe and unavoidable impurities.

Rolling technology is: Heating temperature is 1200-1250 ℃, heat-up time >=200 minute, and soaking time >=30 minute, the roughing start rolling temperature is 1180-1230 ℃, 870-920 ℃ of finish rolling start rolling temperature, finishing temperature 850-890 ℃; 520-620 ℃ of Acc final cooling temperature, speed of cooling 10-20 ℃/s.Thermal treatment process is: tempering temperature 600-690 ℃.

Outstanding advantage of the present invention is that can to produce thickness be the steel plate of 60-100mm specification to the TMCP+ temper and have excellent mechanical property, its tensile strength >=690MPa, ys >=550MPa; Unit elongation >=18%; The impact of collision merit is greater than 120J under-20 ℃～-40 ℃ conditions, and greater than 40%, carbon equivalent is not more than 0.47% to Z to performance; Welding property is good, and production cost is low.

Embodiment

Below in conjunction with embodiment the present invention is done further description.

Embodiment 1:

With intending rolling thickness is that the slab of 300mm is put into process furnace, and the slab tapping temperature is 1240 ℃, and 240 minutes heat-up times, soaking time is 30 minutes, and the chemical ingredients of slab and content (weight percent) are: C 0.087%; Si 0.443%, and Mn 1.75%, and P 0.015%, and S 0.003%; Alt 0.024%, and Nb 0.053%, and V 0.056%, and Ti 0.012%; Cr 0.232%, and Mo 0.118%, and Ce 0.0001%, and surplus is Fe and unavoidable impurities.Be rolled into the steel plate that thickness is 100mm, detailed rolling and thermal treatment process is seen table 1, and its mechanical property is seen table 2.

Rolling and the thermal treatment process of table 1

The mechanical property of table 2 steel plate

Embodiment 2:

With intending rolling thickness is that the slab of 300mm is put into process furnace, and the slab tapping temperature is 1230 ℃, and 240 minutes heat-up times, soaking time is 30 minutes, and start rolling temperature is 1195 ℃; The chemical ingredients of slab and content (weight percent) are: C 0.087%, and Si 0.462%, and Mn 1.74%, and P 0.012%, and S 0.002%; Alt 0.026%, and Nb 0.053%, and V 0.055%, and Ti 0.013%; Cr 0.227%, and Mo 0.116%, and Ce 0.0001%, and surplus is Fe and unavoidable impurities.Be rolled into the steel plate that thickness is 90mm, detailed rolling and thermal treatment process is seen table 3, and its mechanical property is seen table 4.

Rolling and the thermal treatment process of table 3

The mechanical property of table 4 steel plate

Claims

1. an engineering machinery is used steel plate, it is characterized in that chemical composition content is by weight percentage: C 0.05-0.12%, Si 0.15-0.50%, Mn 1.5-1.9%; P≤0.018%, S≤0.005%, Alt>=0.020%, Nb 0.030-0.060%; V 0.030-0.065%, Ti 0.008-0.020%, Cr 0.150-0.30%; Mo 0.08-0.20%, RE≤0.0010%, surplus is Fe and unavoidable impurities.

2. an engineering machinery is with rolling, the thermal treatment process of steel plate; It is characterized in that said steel plate has the described chemical ingredients of claim 1, its rolling technology is following: Heating temperature is 1200-1250 ℃, heat-up time >=200 minute; Soaking time >=30 minute; The roughing start rolling temperature is 1180-1230 ℃, 870-920 ℃ of finish rolling start rolling temperature, finishing temperature 850-890 ℃; 520-620 ℃ of Acc final cooling temperature, speed of cooling 10-20 ℃/s; Its thermal treatment process is: tempering temperature 600-690 ℃, can produce the steel plate that thickness is 60-100mm.