New-style stainless steel solders of material optimize a design

Those who carry part of pair of welding rod coating optimize a design, stoma of welding line of the influence in analysing coating of stainless steel welding rod makes the element of rate and each ingredient the influence rule to porosity, solved the problem of stoma of occurrence welding line, overcame coating of stainless steel welding rod thoroughly the defect of aglow craze.

Increased welding rod length as a result of the adoption of core of mild steel solder at the same time, decreased to change welding rod frequency, can use bigger solder wiring energy, rose to solder greatly efficiency.

Make clear through exam, this welding rod transfers alloy quantity achieves a design to ask, apply metal has welding line frit to be fought admirably ability and integrated and mechanical function are corroded between brilliant.

Keyword: The defect that stoma of aglow; of; of stainless steel welding rod corrodes the stainless steel welding rod that at present our country produces to be put generally in craft sex to be differred quite between; brilliant, its key problem is craze of Yi Fagong of welding rod coating, create the enormous waste of welding rod.

Coating of stainless steel welding rod because the resistor rate of stainless steel is older than mild steel,easy aglow craze is much, at the same time the linear expansion coefficient of stainless steel big, the welding rod when soldering carries very big electricity, solder core arises to many resistor is heated up and expand, when solder core expand deflection exceeds coating be out of shape when ability, coating is about craze.

Should raise stainless steel welding rod to fight aglow function way to there is: ? Emperor apology seeks creek feeling neck is old vast if? of graceful Nao holding the post of imprison is in stuff of metal of low resistance of layer of Tu Yi of surface of core of stainless steel solder, lower the resistor rate of solder core, make the temperature rise of solder core is reduced, what prevent welding rod coating thereby is aglow [1] , the defect of this kind of method is to make the manufacturing technology of welding rod becomes complex, increased; of welding rod cost 2 it is recipe of coating of change welding rod, in order to raise voltage of welding rod electric arc and fused rate, short circuit of drop of frit of change welding rod transfers for broken bits wall [2] , but the effect of this kind of method sometimes not apparent.

If stainless steel welding rod uses core of mild steel solder, the alloy that realizes frit apply metal through the transition of the alloyed powder in coating is changed, lead as a result of the resistor of core of mild steel solder remarkable under core of stainless steel solder, this will reduce generation of solder core caloric greatly, remove the cause with aglow coating, and from go up at all solve coating of stainless steel welding rod aglow craze problem.

When should using core of mild steel solder at the same time, can make the length of stainless steel welding rod increases the length of common welding rod, so soldering efficiency will rise, the utilization rate of welding rod also will increase.

The coating that sexual research is craft of 1 welding rod to solve stainless steel welding rod thoroughly is aglow craze problem, the article uses H core of 08 A solder replaces core of stainless steel solder, manganese of alloying element chromic nickel is joined to wait in welding rod coating, transfer to the middle of welding line through coating alloy.

Hand in the adaptability of direct current source to raise welding rod to be opposite, use acidity coating so, the broken bits department of affirmatory coating is T ｉ O O of ｉ of OS of 2 C ａ 2, according to a few data and experience the suppress after affirmatory preliminary coating recipe gives a batch of welding rod to have a test, discovering the main problem that appears on sex of craft of this welding rod is stoma of welding line easy generation, air hole appears in welding line apparently, from welding line apparently look show horn degree of lip-rounding, and stomatic all around the wall that bright slips, can judge from stomatic feature so give its to be hydric aperture.

Because alloy relies on coating completely to transfer,this welding rod produces hydric aperture is, 50% is as high as to be alloy composition in coating, make the reproducibility of coating very strong, oxidisability is insufficient, bring about the generation of hydric aperture thereby, this is to treat settlement problem urgently, want to optimize a design to coating recipe.

The basis solders metallurgy is academic, come from solder material say, the amount of the oxide in wanting to restrain hydric aperture generation to be about to adjust coating, deoxidizer and fluoride and sort, secure other constituent first so changeless the content that the marble in adjust coating, feldspathic, fluorine changes calcic, cryolite and oxidation iron oxide red goes with achieving the purpose of stoma of removal of hydrogen embrittlement, use orthogonality to express arrangement experiment, undertake to recipe of welding rod coating orthogonality returns to an analysis, pass welding line porosity and coating series yuan the recursive equation between content, beg gave coating best recipe, solved the problem of hydric aperture.

Marble discovers in research, fluorite, oxidation iron oxide red is very remarkable to the influence of hydric aperture, and the change of feldspathic content is not big to stomatic influence.

1.

The effect with the influence oxidation stomatic to hydrogen iron oxide red with 1 oxidation stomatic to hydrogen iron oxide red is particularly distinct, worsened badly the craft sex of welding rod, oxidation releases an oxygen to increase the oxidisability of gas phase when be heated of iron oxide red, decompose O of child F ｅ to also can increase slaggy oxidisability, should reduce the generation of hydric aperture originally, but experimental result rather, because become,the likelihood is when manual arc welding, does hydrogen pass two kinds of ways to dissolve to the middle of the metal: ? Play of Gou of admire of Lu of fish hawk of  of thoroughfare guanidine standing grain grows Huang Qiao  first have Mou of  leap up? of fish hawk of Guo of amaranth asking dumpling 2 it is to pass slaggy layer to enter a metal.

Hydrogen is passed slaggy when transferring to the metal, hydrogen or water above all broken bits of dissolve Yu Rong, with OH - ionic form exists, transfer to the metal by broken bits next.

Basically pass the following two reaction: ? ? O + (OH of 2(of → of O 2-) ← - ) (OH of F ｅ 2+)+2(- ) ← → [F ｅ ] + 2[O] + 2[H] 2 O of F ｅ the affiliation of 3, 2+ grow in quantity of the O 2- that makes broken bits medium and F ｅ , make reaction easy undertake right, the dissolve that makes hydrogen is entered, and make stomatic tendency increases.

1.

The marble after because coating is heated,2 marble enrage the influence of aperture to hydrogen decomposes C ａ CO O of ａ of 3 → C + the protection that the carbon dioxide gas that 2 ↑ of CO produce can strengthen pair of bath, prevent vapor invade, at the same time CO 2 it is oxidisability gas, can reduce the balance concentration of bath hydrogen, reduced hydrogen to invade bath from the first way thereby, reduced the sensitivity of hydric aperture.

1.

The influence fluorite with 3 stomatic to welding line hydrogen fluorite enrages the influence that Kong Youxian writes to welding line hydrogen.

Because become F of ａ of the C in broken bits 2 with S ｉ O following reaction can have when 2 coexistence 22 C of O of ｉ of S of 2+3 of F of 2 C ａ 3+ S of O of ａ S ｉ ｉ F 4 boiling point of 4 generated S ｉ F are low, exist with gaseous state, produce F of ｉ of HS of 4+3 of F of reaction S ｉ to enrage with hydrogen of the atom in gas phase and vapor + HF of 2+4 of O of ｉ of S of 2 O gas can reduce H of 3 4+2 of HFS ｉ F consequently hydrogen is contained to measure in welding line, and reduce hydric aperture liability, from above reaction can see, 2 pairs of fluorite go to S ｉ O hydrogenous effect has very big effect.

1.

The affects feldspar bases with 4 stomatic to welding line hydrogen feldspar is 73%) of ～ of 2(63% of S ｉ O, 2 O of AL 3(17% ～ 24%) , 2 O of K + 2 O of N ａ > 12% , the change of feldspathic content is affected to porosity of welding line hydrogen very small, the span that is feldspar so formerly is small, the impact is less, although,be secondly of feldspathic content raise the oxidisability that is helpful for raising coating, beneficial divides hydric aperture at disappear, but its content increased to also increase pool of silicon Xiang Rong transfer, and silicon is exterior active element, block up hydrogen spills over by bath, because this effect is not apparent.

The design of system of alloy of Nextpage 2 welding line this welding rod basically is used at applying some chromic nickel austenite extensively of steel solder, because this fixes the alloy system of frit apply metal,be ｎ of M of ｉ of N of ｒ of F ｅ C.

Is composition limits the chemistry of metal of apply of welding line frit that article place designs: ? ?004% ～ 008% , c ｒ : 18% ～ 23% , n ｉ : 9% ～ 11% , m ｎ : 05% ～ 1.

5% , s ｉ : 05% ～ 1% , p ≤ 0040% , s ≤ 0030% .

Course of recipe of welding rod coating optimizes a design, the technical properties of welding rod is more satisfactory already, but design a requirement to satisfy composition of metal of apply of welding line frit, in order to improve the organization of welding line and performance, must go up to undertake adjustment to the content of the alloying element in welding rod coating in foundation of former best recipe.

To stainless steel welding rod, basically be the content that adjusts ｎ of ｉ of C ｒ , N, M reach in order to make welding line can match contented and mechanical performance with composition of chemistry of mother capable person be able to bear or endure corrode sex requirement, to achieve a design composition asks, the content of the alloying element in wanting pair of coating is adjusted.

Function of metal of 3 welding line 3.

Organization of metallographic of 1 welding line analysed the bond to this welding rod welding line and welding line organization to have observation below optical microscope, what its metallographic organizes is left the material that it is a mother (the single-phase austenite of 9) of 18 N ｉ organizes 1 C ｒ , bond organization is on the right side of.

Distributinging on austenite matrix organizations of a few strip δ ferrite.

The ｉ of N of = of ｑ of ｅ of ｉ of nickel equivalent N of metal of this apply of welding line frit + 30 C + =131 of 05 M ｎ , ｒ of C of = of ｑ of ｅ of ｒ of chromic equivalent C + =22 of 15 S ｉ , ｑ of C ｒ ｅ / =168 of ｑ of N ｉ ｅ , so welding line metal with photograph δ ferrite is born first caky [4] , solder when bath metal is caky, basically did not fuse with bath bottom by solder mother capable person the grain surface of base metal is the off-the-peg surface that is not initiative form nucleus, this surface makes metal of bath liquid state with columnar the configuration of brilliant grows to welding line center, austenite is in caky the ferrite during is columnar the rich austenite between brilliant changes nucleus of the form in the fluid photograph that forms an element, be brought up to the middle of metal of bath liquid state and ferrite.

The ferrite in bringing about the welding line below room temperature so decreases in great quantities, its are main with vermicular with the layer piece shape is located in columnar brilliant center.

And to welding line center, the temperature gradient in fluid photograph is small, very wide composition super-cooling division can be formed in fluid photograph, at this moment metal of bath liquid state is the off-the-peg surface that is not initiative form nucleus to give birth to a nucleus to produce new grain in fluid photograph interior with the not fused suspension particle in bath.

These grain all around uncrossed, can grow freely, form brilliant waiting for an axis.

And form ferrite finally with the layer piece shape is located in austenite all round.

Function of didymous welding line has the look of ferrite δ photograph beneficial effect, it is to be helpful for those who increase welding line fighting firstly ability; is being corroded between brilliant is δ photograph can prevent austenite welding line secondly caky crackle.

But ferrite δ content cannot pass much, δ → happens below high temperature otherwise σ transforms and fragile change, the optimal content of the ferrite in welding line is 5% .

3.

The chemical composition of metal of apply of frit of 2 welding line and organization control metallization of this apply of welding line frit to learn composition, the composition of frit apply metal already achieved design requirement.

Press measurement technique of ferrite of welding line of stainless steel of austenite of GB 195480(chromic nickel) content of the ferrite in undertaking measuring welding line of definitive edition welding rod, the result makes clear, content of ferrite in welding line is about 6% , achieved design requirement. 3.

The mechanical function of metal of apply of frit of 3 welding line solders by GB 264989(contact is mechanical method of function experiment sampling) undertake sampling, and according to GB 22887 have drawing test, show frit apply mechanical properties of metals is admirable, and plasticity is very good.

3.

Of metal of apply of frit of 4 welding line be able to bear or endure corrode function presses GB 4334584 " vitriolic bluestone corrodes stainless steel experimental method " have a test, sample condition is as welded, sample size is × of 80 ｍ ｍ 3 ｍ of × of 10 ｍ ｍ ｍ , the vitriolic bluestone that adding sample bit having copper the boil in flask of frit fluid circumfluence 16 ｈ , make sure test specimen and cupreous bits are contacted in the round, experiment hind takes out sample, abluent, dry, assess undertakes after bending.

The angle of bend of this sample is spent for 180 ° , the sample after bending is magnifying the observation below the magnifier of 10 times curves outside face, did not discover to crackle is corroded between brilliant.

3.

Sex of craft of 5 welding rod detects detect proof, although this welding rod issues coating in big electric current not aglow also craze, light arc to compare stability, welding line shapes good, without occurrence stoma, broken bits carapace can fall off automatically, frit drop transfers means transfers for short circuit and broken bits wall, splatter smaller, this welding rod integral performance is better.

The welding rod of new-style stainless steel that 4 conclusion develop is passed use core of mild steel solder, adopt alloy system optimize a design, overcame stomatic problem to find the influence pattern with coating stomatic to hydrogen constituent, resolved the weakness of craze of Yi Fagong of coating of welding rod of common stainless steel, technical properties is good.

The experiment makes clear, metal of this apply of welding line frit ferrite δ ferrite + organization of austenite double appearance, have be able to bear or endure outstandingly ability is corroded between brilliant, have good integrated and mechanical performance at the same time, have good promotion value. CNC Milling CNC Machining