On the 30th of steel used for forging and hot stamping machinery parts, cold drawn, heavy and general machinery shaft, rod, rings, as well as on the use of machinery castings, such as cylinder, turbine frame, rolling mill frame and parts machine frame and flywheel. 1 Introduction 30 GB, it is called Steel, DIN standard, it is called C30, ASTM standard, it is called 1030, JIS standard, it is called the 30th steel S30C 2 describes characteristics: Compared with the low-carbon steel, strength, hardness were higher, with good toughness and weldability, this steel is often used in normalizing the state, but also for quenching. Uses: Suitable for hot forging, pressing and cutting plus approach, smaller manufacturing section, discontinuity large parts ≤150 ℃ operating temperature, such as screw, rod, shaft keys, rings, gears, sleeves, etc; cutting good, widely used in automatic machining of bolts, screws, etc.; also required for the manufacture of cold forging parts and weldments; also be used as carburizing, carbonitriding and other parts. 3 mechanical properties of the mechanical properties of the 30th steel: tensile strength σb (MPa) ≥490, yield strength σs (MPa) ≥295, elongation δ5 (%) ≥21, section shrinkage ψ (%) ≥50, the impact energy Akv (J) ≥63, Hardness: no heat ≤179HB, sample blank size: 25mm Heat Treatment: 880 ℃ normalizing, 860 ℃ quenching, 600 ℃ tempered. 4 steel welding performance on the 30th and 45 gauge steel with good bonding among them only the hardness of steel rod, suitable for air-cooled steel, cast: If ICD5,7CrSiMnMoV ... etc. Drawing automobile sheet metal cover mold and large metal sheet metal stamping dies, the tensile parts repair can also be used to make stiff dough. Also in use is also something that needs to be aware of: 1. wet site before construction, welding before drying to 150-200 ° C 30-50 minutes. 2. usually impose above 200 ° C preheated air cooling after welding, then the best possible implementation of stress relief. 3. Multi-layer surfacing place to CMC-E30N base, get better welding results. The main components of hardness HRC 48-52 Cr Si Mn C For current range: Shanghai Kai Kai Xinte steel provide pictures Shanghai Xinte steel provide images diameter and length m / m 3.2 * 350mm 4.0 * 350mm current range (Amp) 70-100 130 -1505 chemical composition of the 30th steel chemical composition: carbon content (C) 0.27 ~ 0.34, manganese (Mn) 0.50 ~ 0.80, nickel (Ni) ≤0.30, silicon (Si) 0.17 ~ 0.37, phosphorus (P) ≤0.035, Sulfur (S) ≤0.035, chromium (Cr) ≤0.25, copper (Cu) ≤0.25