Mild steel A

The Results Confirm That Under The Same Welding Conditions, weld Arc Is Obviously Constricted, the Penetration Is Increased Remarkably And The Width Of Welds Is Reduced A Little After Covering The Activating Flux.

The Emphasis Of This Paper Lies In Introducing Developing The Flux Composition, analyzing Its Influence Factors To The Penetration, and Preliminarily Analyzing The Mechanism For Increased Penetration.

Keywords: A-TIG, weld Penetration, activating Flux, arc Constriction, solder of TIG of Surface Tension0 introductive 　 is in contemporary solder gain ground very much in the law, its advantage is welding line quality tall, use those who reach high quality at nicety to solder commonly solder place. Its are main defect is: Only way solders frit depth; Sensitive to the change of material composition; Manufacturing efficiency is low. In recent years, one kind solder new-styly law - A-TIG (Activating Flux TIG) solder is causing worldwide wife people height takes seriously. A-TIG method is activator of the surface on the exterior besmear in the plank that apply solder, apply again next groovy TIG solder. This method can rise greatly solder frit is deep, use this kind of method and technology to be able to make solder frit is mixed greatly manufacturing efficiency increases 1~3 than groovy TIG solder times, right board thick 3~8mm material need not open groove, can solder finish. because of such, caused black, flower, the height of the country such as day, beauty takes seriously. At present Wukelanbadu solders the institute already used this technology at soldering in the production of the main project construction such as component of nuclear reactor pipe [2] , home considers to just just start. The article undertook in the light of mild steel series experiment studies. 1 experiment method 1.

The board applying solder that this experiment uses 1 material and sample is mild steel, exterior activator material of the foundation basically is SiO2, tiO2, CaO, MgO, halide, cr2O3. Sample size is 20080x6mm1.

Test of 2 experiments means uses solder the brilliant gate that power source leaves production for Tangshansong provides control / deliver direct current amphibious solder power source, solder electric current is 130A, solder speed is 70mm/min. Weighing those who use to take all sorts of part is electronic balance, precision is 0.

01mg. Certain proportion will be pressed with acetone before solder allocated activator agitate is become starchy, with the brush even ground brushs the one aspect of the matter of workpiece. In same solder below the standard, will have coat area and solder without coating area finish. Electric arc of the observation when solder and voltage change, the stand or fall that workpiece surface welding line shapes observes after solder is over, observation the result has a record. Have welding line intermediate zone sample is ground after cut again, the frit that surveys sample broad change of deep, frit. Choose a kind of better prescription, arc length of ordinal change electric arc undertakes soldering, analyse its to affect the pattern. 2 tests result 2.

3 kinds of in affecting this group of experiments activator with 1 fluorite deep to frit content (A1, A2, A3) the profound to frit influence when content of main check fluorite changes, particular test result sees a table 1 watch 1 fluorite content notes to the influence of bath appearance: The data presentation before " of → of the " in the watch does not have the test result when activator, the test result after the activator on the data presentation besmear from the back. Fluorite content if the graph shows 1 times,to soldering frit affects greatly: Graph 1 fluorite content to soldering frit is affected greatly from the graph 1 in we can see what Shi Han measures Sui Ying increase, frit increases multiple greatly to be reduced instead. 2.

2The influence with NaCl content profound to frit change this group experiment recipe of 6 kinds of activator (B1-B6) in the content of NaCl is by small arrive big, concrete experimental result sees a table the influence besmear of content of 2 watches 2 NaCl to bath appearance has recipe B1-3 try board the frit that after soldering, gets is deep if the graph shows 2 times,the picture with the does not have activator dark frit that answers relatively with its contrasts: (A) the bath appearance that does not have activator (B) the bath figure that has activator pursues the after trying board solder frit that 2 besmear have activator B3 is deep contrast (I=150A) NaCl content to soldering the influence with profound frit is like a graph content of 3 3 NaCl that show a picture is opposite solder frit is deep: Along with the addition of NaCl content, frit also increases multiple greatly subsequently. 2.

A group of better recipes that the before affecting us to choose in order to experiment with 3 deep to frit arc length gets will do these two groups of tests, if express,about the test result of arc length 3 are shown. Express 3 along with arc length metabolic activator is opposite the influence of bath appearance is opposite as the metabolic activator of arc length the influence of bath appearance shows a picture 4 times like the graph the 4 metabolic activator as arc length are right the influence of bath appearance from the watch 3 with the graph 4 in report goes out: The frit when growing for 3mm about in arc length is deep increase the most apparent, and solder electric arc is contractive and apparent, solder figuration is good. 3, the experiment phenomenon of discussion summary above and test result, can think exterior activator makes solder frit is deep addition main reason has the following 3 respects. Apt of Wu Kelan's scholar the first kind of reason, and American scholar thinks the 2nd kind of reason is frit deep addition the mainest reason. Make frit deep to exterior activator on international at present the viewpoint that addition mechanism has not united. 3. Systole of 1 electric arc brings about frit deep increasing electric arc to contract is the phenomenon that the naked eye in the experiment can observe. When soldering on activator coating, electric arc can have apparent systole, cause current density concentration, electric area is contractible, at the same time electric arc force also adds, make frit finally deep increase. The reason with contractive electric arc has 3 to plant likelihood [1, 3, 4] (1) the central area in electric arc, of the element of temperature prep above of electric arc decompose temperature, gas and activator atom are mixed into the electron by ionization ionic. In arc column colder periphery region, the matter that is evaporated still exists with element and the atomic form that are decomposed, the electron of atomic abundantly adsorption that is decomposed, form anion, the electron that makes periphery area regards main electric conduction as material decreases, electric capacity drops, make electric arc contractive. (2) each constituent of the activator that uses because of us is much more atomic element, produce hot solution to leave below electric arc atmosphere so, heating up solution to leave is endothermic reaction, the ground is the so least voltage principle, make electric arc contractive. (3) because coating material itself is not electric, what compare a metal because of the frit boiling point of coating material again is tall, be in electric arc center only so the area with higher temperature, have a metal evaporate, form zincous stain, namely the existence of coating reduced zincous stain area, make electric arc contractive thereby. 3. The influence of gradient of 2 surfaces tension is belonged to in bullion and in a lot of alloy, exterior tension follows the addition of temperature and reduce, namely D σ / DT<0, because of exterior tension big local liquid flows very hard, it is the liquid with exterior small pulling force flows to the place with exterior large pulling force so. In bath, central area temperature is high, reason bath metal flows, form wide and shallow frit so deep. Should add in bath have active element (like S, o) when, d σ / DT>0, the liquid flows, form deep and narrow frit so deep. 3. The addition that 3 heat input is in experiment process, of great majority try board the addition that there is different rate in voltage of the electric arc after the activator on besmear, and the electric current of electric arc is constant and constant, hot input increases, be helpful for the addition with deep frit for certain. Press the several value of a quantity that electric arc voltage increases, the input is heated up to increase at most than before in this experiment 15% , and actual frit can amount to 300% above greatly. Although visible hot input makes bath increases somewhat, but either frit is deep increasing main factor. 3. 4 discuss further so electric arc systole and gradient of bath surface tension which on one hand is the impact bigger? We try with what besmear has activator board undertake small-power electron beam solders experiment. Because electron beam solder does not have electric arc, need not consider electric arc systole. Have the effect of exterior tension only to electron beam so. Experimental result is electron beam solder deep to frit impact is very little, the change that also expresses gradient of area pulling force with respect to preliminary specification adds deepness effect greatly to bath frit very small. 4 conclusion experiment through soldering to carbolic steel "A-TIG" , following verdict get below this experiment condition: (1) solder of TIG of carbolic steel convention adds activator, can make frit deep increase 1~2 times. (2) in solder of carbolic steel A-TIG, make solder frit is deep addition main reason has electric arc systole and exterior tension gradient two respects, those who have main effect is electric arc systole. (3) in A-TIG solder, frit is deep increase to still be concerned with arc length. Arc length is controlled in 3mm optimal. (4) activator composition is different, frit is deep increase degree to also differ. CNC Milling CNC Machining