Electrode classification of the material in the Welding Electrode drug skin welding classification from different angles. From the perspective of welding metallurgy, according to the basicity of the slag welding rod is divided into acid electrode and alkaline welding rod; the main component of the electrode drug skin electrode is divided into a lime-titania type electrode, ilmenite type electrode, low hydrogen type electrode iron powder electrode. [Such as the tensile strength of deposited metal, the chemical composition of type> from the standardization point of view, in accordance with the characteristics of the electrode, the electrode is divided into many types and different levels in order to determine the electrode of a variety of type. From the use of perspective, but also the electrode is divided into ten categories of structural steel welding rod, heat-resistant steel rod and stainless steel electrode. Now a variety of classification methods are described below. (A) of the slag basicity classification Will electrode in the actual production is usually divided into two categories, acid electrode and alkaline electrode (also known as low-hydrogen electrodes, which are mainly according to the basicity of the slag, ie slag etching of oxides and alkaline oxidation the proportion of objects classified branded slag in acidic oxide ^ for a major proportion "of the acid electrode, and vice versa is the alkaline electrode. To compare the welding performance of the Shang Yi acid electrode arc soft, little spatter, good slag fluidity and coverage, therefore, weld appearance constricted view of the solder wave is close, forming smooth; alkali even electrode metal transfer short-circuit transition arc is not stable enough, the poor coverage of the melting economy convex weld shape and weld appearance corrugated rough, but in the upward vertical position welding, easy to operate. Acidic electrode coating contains more iron oxide, titanium oxide and silicon oxide, etc., strong oxidation in the welding process, to alloy cable burning more You in the weld metal oxygen and hydrogen content more, and thus ductility, toughness low acid electrode is generally both AC and DC. The typical acid electrode is] 422. Alkaline electrode coating Cao containing large amounts of marble and fluorite, and the ferroalloy more deoxidizer and alloying agent, drug leather sufficient deoxidation capability. Furthermore, the alkaline electrode depends mainly on the marble and other carbonate decomposition of carbon dioxide as shielding gas, compared with the acid electrode, lower partial pressure of hydrogen in the atmosphere in the arc column, and the calcium fluoride in fluorite in Gao temperature and hydrogen combined into a gasification hydrogen (only plants), thereby reducing the hydrogen content in the weld, and alkaline welding rod is also known as low-hydrogen electrodes. However, due to the fluorine anti-ionization, so the alkaline electrode arc stable burning, generally only DCRP <electrodes Received positive> welding, only when the drug skin contains large amounts of stable arc agent only when the AC and DC. With the Zang sexual Welding Rod, due to less oxygen and hydrogen content in weld metal, non-metallic inclusions is less, so Gao ductility and impact toughness. General welding of important structures (such as to withstand the dynamic load of the structure) or more rigid structure and the poor weldability of steel alkaline electrode. Typical of the alkaline electrode is] 507. Acid electrode and alkaline electrode process performance are shown in Table 1-8. At room temperature, per 1006 melt diffusible hydrogen content in the deposited metal, alkaline electrode 1? 101 111 ^ acid electrode, compared with 17 to 5011 ^. Various types of electrodes deposited gold shavings in the hydrogen content shown in Figure 1-5. The oxygen content of the various electrodes of the weld metal (non-metallic oxides from the weld metal, & 0, translation might 00,3 丨 ^, the total oxygen are as follows: cellulose-type titanium oxide type, ilmenite- 0.06 "" 0.100 ^ 0 ^ 100; iron oxide type it? force .130; low hydrogen type 0.028 ^) 6? "40 ^.
(B) of the drug skin Electrode drug skin can be referred to as paint, spread it to the solder core is mainly to facilitate the welding operation and to ensure that the deposited metal has a certain composition and performance as Ah. The main role of the drug skin is: (!) To ensure that the arc focus, stability, droplet metal easy transition; (^) Caused an also hide or neutral atmosphere around the arc to prevent oxygen and nitrogen in the air into the deposited gold dust; (^) Generated slag evenly cover the surface of the weld metal, slowing the cooling rate of weld metal and get a good weld profile; ("To ensure that the slag melting point, viscosity, density, so that the Welding Electrode can be carried out for all position welding easy to carry out special operations, such as downward vertical position welding; (^) Drug skin under high temperature of the arc series metallurgical chemical reaction occurs, with the exception of the too-oxide and 3, "and other harmful impurities can also be added in the appropriate alloying elements to ensure that the deposited metal with the required mechanical properties or other special properties (such as corrosion resistance, heat resistance, wear resistance, In addition, a certain amount of iron in the electrode drug skin can be improved welding performance, or mention Gao deposition efficiency. Electrodes drug skin oxides, carbonates, silicates, organics, fluoride, ferro alloys and chemical products can be used hundreds of kinds of raw material powder mixture according to the proportion of a certain formula. Various raw materials in accordance with its role in the Welding Rod drug skin can be divided into the following categories. Arc stability agent to make the electrode easy arc in the welding process can maintain stable arc burning. As stable arc agent the materials mostly contain a certain amount of substance of low ionization potential elements, such as rutile, titanium dioxide, ilmenite, ilmenite, feldspar, sodium silicate (containing potassium, sodium and other alkaline earth metal silicate salt〗, in addition to aluminum-magnesium alloy. With certain physical and chemical properties of slag welding (Magic slagging agent can be formed to protect the weld pool and improve weld forming slag basicity on the welding performance and weld metal of the physical and chemical properties have a great impact. slagging agent, mostly carbonates, silicates, oxides and fluorides, such as marble, fluorite, dolomite, magnesite, feldspar, white clay, mica, quartz sand, rutile, titanium dioxide, titanium ore, ilmenite, iron ore, and cryolite. some material on the slag viscosity, the fluidity of the thin residue can play a role, such as fluorspar, cryolite, manganese. (Magic Deoxidizer through the welding process, metallurgical and chemical reaction to reduce the oxygen content in the weld metal to improve the weld properties, mainly containing oxygen affinity elements ferroalloy and metal powder, such as ferromanganese, silicon iron, neodymium iron, aluminum and iron, magnesium powder, aluminum-magnesium alloy, calcium alloys and graphite. ((1) gas agent in the arc under high temperature and can decompose to release gas in order to protect the arc and weld pool to prevent the invasion of Zhou Min limonene gas oxygen and nitrogen. Commonly used gasification agent, carbonate and organic matter. such as marble, dolomite, magnesite, barium carbonate, wood flour, cellulose, starch and resin and so on. (^) Alloying agent used to compensate for the burning of alloying elements in the welding process to weld transition alloying elements, to ensure that the weld metal chemical composition and performance. Commonly used in all kinds of ferroalloy and metal powder as an alloying agent, such as ferromanganese, ferrosilicon, Ferrochrome, molybdenum, vanadium, iron, niobium, iron, boron, iron, manganese, Jincheng chromium, nickel powder, tungsten powder, rare earth ferrosilicon, etc.. (... By plastic lubricant to increase the plasticity of the process of drug skin powder coated electrode pressure, slip and mobility to improve the quality Xia electrode pressure coated to reduce the eccentricity of these materials Bu often soldiers are Mao - given the expansion of the absorbent shield heart relies on or has a certain degree of flexibility, slip resistance, such as mother, synthetic mica, talc, clay,: -: titanium dioxide, white clay, wood flour, bentonite, sodium carbonate, sepiolite, silk Wan mother. alginic acid salt and ^ (:. (!) Binder drug skin powder pressure coating process has a certain viscosity, firmly bonding with the core of the welding and electrode drug skin with Mao certain strength after drying. The main binder of water glass (potassium, steel and lithium water glass] and phenolic resin and so on. Of course, the above is only a simple classification of the main role of each material, in fact, a material can have several roles. For example, the marble arc high temperature decomposition of 00 and 00 ^ (^ play a protective role, 00 slag, so the marble made the gas agent and slagging agent. Again, manganese deoxidizer In addition to deoxy excess manganese penetrated welds, since the role of the alloying agent the same time, as deoxidation products from 110 slagging.