CN107584212A

CN107584212A - A kind of laser silk filling butt welding Thin Specs SUS430 cold drawing methods

Info

Publication number: CN107584212A
Application number: CN201710950119.9A
Authority: CN
Inventors: 段秀峰; 王月省; 韩佳明; 段维芳; 曹胜
Original assignee: Shanxi Taigang Stainless Steel Co Ltd
Current assignee: Shanxi Taigang Stainless Steel Co Ltd
Priority date: 2017-10-13
Filing date: 2017-10-13
Publication date: 2018-01-16

Abstract

The present invention relates to the laser butt welding field of SUS430 ferrite cold drawings.A kind of laser silk filling butt welding Thin Specs SUS430 cold drawing methods, the power for reducing laser welder is 3.3 kW, simultaneously, Z axis offset is adjusted to+0.57 mm, adjustment gap is+0.10 mm, the speed that fills silk is adjusted to 1.9 mpm, and post weld heat treatment temperature is set to 830 DEG C, and Thin Specs refer to that thickness is 0.55 ~ 0.65 mm.The beneficial effects of the invention are as follows：The weld seam of 0.55 ~ 0.65 mm Thin Specs SUS430 cold drawings, which can be ensured, can pass through completely 14 groups of jockey pulleys and 300 m length, the DEG CLu areas of furnace temperature 900 without broken belt.

Description

A kind of laser silk filling butt welding Thin Specs SUS430 cold drawing methods

Technical field

The present invention relates to the laser butt welding field of SUS430 ferrite cold drawings.

Background technology

In order to meet tandem mills rolling demand and continuous production, RAP wire bondings seam is using laser welder, steel plate butt welding Connect.It is CO2 that gas, which occurs, for RAP line lasers, and peak power is mainly female using " keyhole effect " fusion up to 12000 W, welding process Material, fast with speed of welding, silk filling amount is small, and fusion penetration is than big, and energy density is concentrated, weld seam HAZ regions very little, weld seam fusion performance Well, the features such as face of weld beautiful appearance.Welder equipment design throat thickness scope is 0.7 ~ 6.0 mm.

In January, 2015, stainless steel declinning market, the stainless cold rolling mill 1#RAP lines amount of rolling row of Taiyuan Iron and Steel Co. are discontented.Therefore, 1# RAP lines use as cold line, i.e., raw material be cold drawing, and sky is crossed milling train, do not rolled, and using the annealing on unit, pickling, smooth set It is standby.Stainless cold rolling mill arranges 1#RAP lines to produce the SUS430 cold drawings after other unit rollings, and thickness range is 0.7 ~ 2.0 mm. SUS430 steel grades belong to middle chrome ferritic stainless steel, and carbon content is higher, lack stable element titanium, niobium, and in welding, commissure is brilliant Grain is easily thick, produces intermetallic phase, and welding difficulty is big.Meanwhile the SUS430 cold drawings after rolling, due to rolled hardening, processing Stress is present, and grain structure changes, and elongation percentage is low, increases welding difficulty.

0.55 ~ 0.65 mm thickness exceeds laser welder capacity of equipment lower limit, and high to equipment precision requirement, sweating heat is defeated It is somewhat excessive to enter amount, weld seam occurs as soon as hole, it is impossible to met line requirement.

The content of the invention

The technical problems to be solved by the invention are：How the RAP line laser weldering of welding 0.7 ~ 6.0 mm thickness is used in Machine can complete the welding to 0.55 ~ 0.65 mm Thin Specs SUS430 cold drawings.

The technical solution adopted in the present invention is：A kind of laser silk filling butt welding Thin Specs SUS430 cold drawing methods, reduce and swash The power of welding machine is 3.3 kW, meanwhile, Z axis offset is adjusted to+0.57 mm, adjustment gap is+0.10 mm, and fill silk speed Degree is adjusted to 1.9 mpm, and post weld heat treatment temperature is set to 830 DEG C, and Thin Specs refer to that thickness is 0.55 ~ 0.65 mm,.

The beneficial effects of the invention are as follows：The weld seam of 0.55 ~ 0.65 mm Thin Specs SUS430 cold drawings, which can be ensured, smoothly to be led to Completely 14 groups of jockey pulleys and 300 m length, the DEG CLu areas of furnace temperature 900 are crossed without broken belt.

Brief description of the drawings

Fig. 1 is using the weld seam after the inventive method welding machine laser silk filling mm Thin Specs SUS430 cold drawings of butt welding 0.55 ~ 0.65 Metallographic structure figure.

Embodiment

It must assure that mother metal energy density in 105 ~ 107 W/cm2 during stainless steel welded.For 0.55 ~ 0.65 mm Specification SUS430 ferrite cold drawings, heat input is excessive, and energy density easily exceeds the upper limit, causes weld seam hole occur.Pass through Laser power is reduced, plays obvious action in terms of thermal weld stress amount is reduced, reduce hole, but laser power can only drop It is low to 3.3 kW, it is unstable less than 3.3 kW lasing light emitters, there is laser strobe phenomenon.But 3.3 kW lasing light emitters are to maintain, heat is defeated It is so excessive to enter amount times, energy density can also exceed the upper limit, cause weld seam hole occur so also needing to carry out other adjustment.

Z axis is vertical SUS430 ferrites cold drawing cold drawing direction, and laser spot is adjustable in the high and low position that this side up 's.Z axis mechanical zero position is positioned at the upper surface of the lower clamping platform in outlet, and Z axis focal position is in plate when different thicknesss of slab weld Utilization ratio of laser energy highest during material surface location, therefore Z axis is usually set to sheet metal thickness value.But for Thin Specs The cold drawing of (0.55 ~ 0.65 mm), it is necessary to offset is added, further to reduce thermal weld stress amount.By test of many times, It was found that when offset is+0.57 mm (close to thickness of slab), hole can be effectively reduced.

The gap adjustment of cold drawing is particularly important during welding, and gap width is calculated by linear encoder, and defines mechanical zero, Numerical value is positive and negative adjustable.For thickness when 1.0 below mm Thin Specs weld, gap is too small to clamp welding line joint mutability in welding process Shape, appearance of weld are bad.By test of many times, for 0.55 ~ 0.65 mm specifications, filled silk using positive gap value (+0.10 mm) Welding, insert high nickel bare welding filter metal lifting welding performance.

Fill silk, there are two effects, first, by adding MG82 welding wires, improve the extension property of weld seam；Second, by welding Filler is added at seam, throat thickness " can be thickened ", reduces welding difficulty.Fill silk speedSelection need calculate wire feed supply Give amount K：, wherein, D is gage of wire,For speed of welding,For strip average thickness,For strip absolute interstitial.Gap increases, the increase of thermal weld stress amount, caused solid-liquid transformation volume residual quantity increase, Metallic vapour produces plasma gas increase.Gap is timing, it is necessary to wire feed than controlling more than 120%.In view of 0.6 mm The situation of the difficult weldering of thin material, specially increases to 150% by wire feed ratio, with " thickening " throat thickness, must be filled silk finally speed by above formula Degree is about 1.9 mpm.

The setting of post weld heat treatment temperature is most important, on the one hand the whether good of weldquality depends on fusion area （Welding process determines）, on the other hand depending on HAZ（Heat affected area）, and post weld heat treatment divides the stress for improving HAZ regions The influence such as cloth and toughness is very big.475 DEG C of fragility in view of SUS430, occur in 550 ~ 820 DEG C of long-term heating σ phases with And more than 900 DEG C be extremely easily roughened and be difficult to eliminate, so post weld heat treatment temperature section must accurately control control, protect Card heating and cooling procedure are as fast as possible.Based on factors above, annealing electric current, speed are set to 95A, 9.5 mpm, so It ensure that 0.55 ~ 0.65 mm specification strip steel upper and lower surface annealing temperatures are rapidly achieved 830 DEG C, and be cooled fast to room temperature.

5 aspects adjust more than, and we have found out the SUS430 ferrite cold drawings of a set of 0.55 ~ 0.65 mm specifications Welding condition.As a result weld seam hole disappears, and above weld seam is not broken three times at positive and negative curved more than 90 ° angles manually, meets Produce the level weld seam requirement of cold drawing.

Claims

A kind of butt welding Thin Specs SUS430 cold drawing methods 1. laser fills silk, it is characterised in that：The power for reducing laser welder is 3.3 KW, meanwhile, Z axis offset is adjusted to+0.57 mm, adjustment gap is+0.10 mm, and the speed that fills silk is adjusted to 1.9 mpm, is welded Heat treatment temperature is set to 830 DEG C afterwards, and Thin Specs refer to that thickness is 0.55 ~ 0.65 mm.