CN101559541B - Test method and device for weld seam alloying in gas shielded welding - Google Patents

Abstract

The invention relates to a test method and a device for weld seam alloying in gas shielded welding, which solve the problems of providing a new way on the research on the weld seam alloying by parent metal other than the gas shielded welding of a welding wire, selecting over 50 percent of the weld seam metal from the parent metal, and generating necessary changes in the chemical compositions of the weld seam due to different parent metals. The technical proposal comprises the followings steps that: a test plate without a welding groove is placed between a base plate and pressure plates of thetest device, and the weld seam is arranged between two pressure plates; the test steel plate is tightly pressed by the pressing of the test device; the weld seam on one surface of the test plate undergoes first pass gas shielded welding by a common welding wire with the weld heat input of 14 to 22 KJ/cm; when the weld seam is naturally cooled down to the temperature of less than or equal to 150 DEG C, the test plate is turned over and tightly pressed, and the weld seam of the test plate undergoes first pass welding; and when the weld seam is naturally cooled down to the temperature of less than or equal to 150 DEG C, the weld seam undergoes tests of hardness, impact, metallic phase and the like. The method and the device have the advantages of performing the test without preparing a gas protection welding wire and researching an effective method on the research on the toughness of the shield welding seam.

Description

The experimental technique of weld seam alloying in gas shielded welding and device thereof

Technical field

The present invention relates to gas shielded welding method, more belong to the experiment usefulness method and the device thereof of weld seam alloying in gas shielded welding.

Background technology

At present, the alloying research that gas is protected weld seam generally is to be undertaken by developing new welding wire, though this method from welding wire to weld seam alloy transition rate height, comparatively reliable, the welding procedure wide accommodation, its weak point:

(1) welding wire production process complexity needs to smelt, waters that ingot, billet rolling, wire rod are rolling, complicated procedures of forming and equipment such as drawing and copper facing, especially when the higher gas shield welding wire of development alloy content, also needs during drawing through annealing in process repeatedly;

(2) make gas shield welding wire by small lot and carry out alloying research cost height, the length consuming time that gas is protected weldering;

(3) even sometimes can't carry out owing to lacking the wire rod making apparatus, small lot wire rod making apparatus is low because of production efficiency, energy consumption is big, suffers exit substantially in China;

(4) some alloy system wire rod cannot be drawn into silk because of drawing property is bad.

In addition, the research of the influence of alloying element butt welded seam intensity is more thorough, and there is document to develop corresponding Forecasting Methodology, and be used widely, but the influence of alloying element butt welded seam toughness is more complicated then, also reliable without comparison at present method predicts that to toughness main dependence welded experiment.

From last surface analysis, traditional research method that gas guarantor weld seam carries out alloying there is too many limitation by the welding wire of making different-alloy content.Therefore it is very meaningful to explore a kind of gas guarantor welding seam alloying research new technology.

Summary of the invention

The problem to be solved in the present invention: by making the thin plate of different-alloy content, adopt appropriate gas to protect the weldering welding procedure, make weld metal come from mother metal more than 50%, the weld seam chemical composition produces needed variation because of mother metal is different; By mother metal is not the new way of the weld seam alloying in gas shielded welding research of welding wire.

The technical measures that address the above problem

A kind of experimental technique of weld seam alloying in gas shielded welding; this method is by making the test welding steel of different-alloy content; and adopt following gas shiled welding step; make weld metal come from mother metal more than 50%; the weld seam chemical composition produces needed variation because of mother metal is different; by mother metal just the gas of welding wire protect weldering and carry out welding seam alloying research, its gas is protected welding step:

1) thickness that will not have a welding groove is that the test welding steel of 6～8 millimeters thick is placed between the backing plate and pressing plate of experimental provision; Weld seam is arranged between two block pressur plates of symmetry, and make the center line of weld seam and backing plate upper groove center line point-blank;

2) exert pressure through experimental provision the test welding steel is closely compressed, and will make the test welding steel keep smooth;

3) use solid wire, with the commissure that 14～22KJ/ centimetre weld heat input designs on the one side of test welding steel, the employing percent by volume is 20%CO ₂Add rich argon or the CO of 80%Ar ₂Gas is made protection gas and is welded a time;

4) treat that weld seam naturally cools to≤150 ℃ the time, the pressure apparatus of experimental provision unclamped, and will test the welding steel turn-over, and make this face axis of a weld of setting and the weld seam that has welded on same straight line; After pressing plate is in place, will tests welding steel again and compress, and keep smooth;

5) still use solid wire, with the commissure welding that 14～22KJ/ centimetre weld heat input designs on the reverse side of test welding steel, the employing percent by volume is 20%CO ₂The rich argon that adds 80%Ar is made protection gas;

6) treat that weld seam naturally cools to≤150 ℃ the time, the pressure apparatus of experimental provision unclamped, and takes out the test welding steel;

7) butt welded seam carries out hardness, impact, metallographic test, and analysis and research gas is protected the influence of solder alloy element butt welded seam structure property.

The present invention compared with prior art, its characteristics are mainly to rely on from steel plate to weld seam transition alloy; Composition of weld line and tissue change because of the variation of mother metal composition, and sweating heat process and deposited metal welding condition are approaching; The welding seam tissue capability result of the test is reliable; Need not make gas protecting welding wire, avoid gas shield welding wire and made difficult problem, convenient, saving; A kind of effective ways that gas is protected welding seam toughness of studying have been explored.

Description of drawings

Fig. 1 is the structural representation of the device of gas shield welding wire alloying experimental technique

Fig. 2 is the plan structure schematic diagram of Fig. 1

The specific embodiment

Be described in detail below in conjunction with accompanying drawing:

The invention process flow process:

Test steel smelting and casting → the be rolled into thick test welding steel of 6～8mm → carry out on experimental provision positive and negative gas is protected welding, and (protective gas is that percent by volume is 20%CO ₂Add rich argon or the CO of 80%Ar ₂Gas) → the welding seam tissue capability analysis.

Welding condition:

The width of experiment welding steel is that the steel plate of 150～250mm is advisable, and this routine steel plate width is 180mm; Gage of wire is 1.2mm; Adopt steel plate square groove positive and negative gas to protect welding;

Now describe the invention process process and verification experimental verification in detail.

(1) test steel smelting and casting.Welding seam alloying research institute needs material quantity few, so adopt the port steel to get final product, the composition of steel is determined according to the research needs.What this project adopted is the 50kg vacuum drying oven, can accurately control the main alloying element content of steel, and can control gas content.Smelted 5 stove systems, weld seam chemical composition that chemical composition is as shown in table 1, table 2 is the experiment welding condition, table 3 is the experiment detection and percentage by weight (wt%), table 4 are tested the weld hardness (HV that detects ₁₀) and calculate tensile strength (MPa), table 5 weld impact test result, table 6 weld structure.

2, Han Jie device

Backing plate 3 by the band groove of placing on supporting plate 1, the supporting plate 12 is formed.It is a center line in the commissure that is provided with on the backing plate 3 with design on the test welding steel, places pressing plate 4 in its bilateral symmetry, and the pressing plate 4 on every limit is 2, is provided with screw pressure device 5 on every.

3, a kind of experimental technique of gas shield welding wire alloying, its step:

1) thickness that will not have a welding groove is that the test welding steel of 6～8 millimeters thick is placed between the backing plate 3 and pressing plate 4 of experimental provision; Weld seam is arranged between two block pressur plates 4 of symmetry, and make the center line of weld seam and backing plate 3 upper grooves 2 center line point-blank;

2) exert pressure through the screw pressure device 5 of experimental provision the test welding steel is closely compressed, and will make the test welding steel keep smooth;

3) use solid wire, with the commissure that 14～22KJ/ centimetre weld heat input designs on the one side of test welding steel, the employing percent by volume is 20%CO ₂Add rich argon or the CO of 80%Ar ₂Gas is made protection gas and is welded a time;

4) treat that weld seam naturally cools to≤150 ℃ the time, the screw pressure device 5 of experimental provision unclamped, will test the welding steel reverse side, and make this face axis of a weld of setting and the weld seam that has welded on same straight line; After pressing plate 4 is in place, will tests welding steel by screw pressure device 5 again and compress, and keep smooth;

5) still use solid wire, with the commissure welding that 14～22KJ/ centimetre weld heat input designs on the reverse side of test welding steel, the employing percent by volume is 20%CO ₂Add rich argon or the CO of 80%Ar ₂Make protection gas;

6) treat that weld seam naturally cools to≤150 ℃ the time, the spiral of experimental provision or the pressure apparatus 5 of saddle weight formula unclamped, and takes out the test welding steel;

7) butt welded seam carries out tests such as hardness, impact, metallographic, and analysis and research gas is protected the influence of solder alloy element butt welded seam structure property.

Table 1 test steel chemical composition (wt%) and specification (mm)

Sequence number	C	Si	Mn	P	S	Cr	Ni	W	Cu
										1	0.105	0.86	1.72	0.013	0.0039	0.63	/	/	0.29
2	0.100	0.44	1.14	0.011	0.0036	0.53	/	/	0.31
										3	0.087	0.49	1.80	0.008	0.0036	0.64	1.41	0.37	0.41
4	0.081	0.44	1.29	0.007	0.0040	0.53	1.19	0.35	0.35
										5	0.079	0.35	1.25	0.008	0.0039	0.43	0.87	/	0.30

Table 2 welding condition

Table 3 weld seam chemical composition (wt%)

Numbering	C	S	Re	W	Si	Mn	Cu	Cr	Ni	Ti	Mo
												1	0.085	0.0079	/	/	0.72	1.40	0.22	0.40	/	/	/
2	0.097	0.0043	/	/	0.64	1.52	0.34	0.51	0.43	/	/
												3	0.095	0.0040	/	/	0.74	1.41	0.24	0.41	/	0.056	/
4	0.088	0.0035	0.013	0.25	0.48	1.58	0.39	0.53	1.22	0.038	/
												5	0.080	0.0028	0.012	0.26	0.42	1.47	0.29	0.38	0.87	0.032	0.070
7	0.081	0.0035	/	/	0.42	1.37	0.33	0.40	0.89	0.019	/
												8	0.073	0.0043	/	/	0.35	1.20	0.22	0.27	0.55	0.012	0.068

Table 4 weld hardness (HV ₁₀) and calculate tensile strength (MPa)

Annotate: computational methods adopt document (number of patent application 200810236873.7) method to carry out.

Table 5 weld impact test result

Annotate: specimen size is 5 * 10 * 55 (mm).

Table 6 weld structure

Compare 2# and 6#, 4# and 7#, three groups of result of the tests of 5# and 8#, every assembly welding silk, protective gas and welding procedure are identical, but have only the mother metal difference.As can be seen: during the mother metal chemical composition change, the weld seam chemical composition produces respective change, and the toughness of weld seam, hardness and metallographic structure all have significant change.By selecting the mother metal and the welding wire of different chemical composition, obtain the weld seam of different chemical composition and structure property, studied welding seam alloying effectively.

Detect through butt welded seam, its as a result weld metal come from mother metal more than 50%, have 1～2mm overlapping between positive and negative weld seam.

Claims (1)

1. the experimental technique of a weld seam alloying in gas shielded welding; this method is by making the test welding steel of different-alloy content; and adopt following gas shiled welding step; make weld metal come from mother metal more than 50%; the weld seam chemical composition produces needed variation because of mother metal is different; by mother metal just the gas of welding wire protect weldering and carry out welding seam alloying research, its gas is protected welding step:

1) thickness that will not have a welding groove is that the test welding steel of 6～8 millimeters thick is placed between the backing plate and pressing plate of experimental provision; Weld seam is arranged between two block pressur plates of symmetry, and make the center line of weld seam and backing plate upper groove center line point-blank;

2) exert pressure through experimental provision the test welding steel is closely compressed, and will make the test welding steel keep smooth;

3) use solid wire, with the commissure welding that 14～22KJ/ centimetre weld heat input designs on the one side of test welding steel, the employing percent by volume is 20%CO ₂The rich argon that adds 80%Ar does to protect gas to weld a time;

4) treat that weld seam naturally cools to≤150 ℃ the time, the pressure apparatus of experimental provision unclamped, and will test the welding steel turn-over, and make this face axis of a weld of setting and the weld seam that has welded on same straight line; After pressing plate is in place, will tests welding steel again and compress, and keep smooth;

5) still use solid wire, with commissure welding a time that 14～22KJ/ centimetre weld heat input designs on the reverse side of test welding steel, the employing percent by volume is 20%CO ₂Add rich argon or the CO of 80%Ar ₂Gas is made protection gas;

6) treat that weld seam naturally cools to≤150 ℃ the time, the pressure apparatus of experimental provision unclamped, and takes out the test welding steel;

7) butt welded seam carries out hardness, impact, metallographic test, and analysis and research gas is protected the influence of solder alloy element butt welded seam structure property.

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