AISI 1212 Steel, hot rolled

AISI 1212 Steel, hot rolled, 19-38 mm round Product Information -:- For detailed product information, please contact sales. -: AISI 1212 Steel, hot rolled, 19-38 mm round Synonyms -:- For detailed product information, please contact sales. -:

AISI 1212 Steel, hot rolled, 19-38 mm round Product Information -:- For detailed product information, please contact sales. -: ### **Product Introduction: AISI 1212 Steel, Hot Rolled Round Bar (19-38 mm)** **Overview** AISI 1212 is the global industry benchmark for free-machining steel, supplied as a **hot rolled round bar** in the diameter range of **19-38 mm**. This low-carbon, resulfurized and rephosphorized steel is engineered specifically for one primary purpose: to enable the fastest, most cost-effective, and highest-volume machining possible. Its "standard" 100% machinability rating serves as the reference point against which all other steels are compared. Supplied in the economical as-rolled condition, AISI 1212 offers an unparalleled combination of easy chip formation, excellent surface finish on machined parts, and consistent performance in automatic screw machines and CNC lathes, making it the undisputed choice for mass-produced, non-structural components. **Key Features & Advantages** * **Benchmark Machinability (100% Rating):** AISI 1212 defines the 100% machinability index. Its optimized sulfur and phosphorus content produces short, broken chips, allows for maximum cutting speeds and feeds, minimizes tool wear, and significantly reduces machining time and cost. * **Superior Surface Finish:** Produces excellent surface quality directly from machining operations, often eliminating the need for secondary finishing such as grinding or polishing. * **High Production Efficiency:** Enables manufacturers to achieve the shortest possible cycle times, lower power consumption, and extended tool life, translating directly to lower per-part costs in high-volume production. * **Excellent Consistency:** Provides predictable and uniform machining behavior from lot to lot, which is critical for stable, automated manufacturing processes. * **Wide Availability & Cost-Effectiveness:** As the most common free-machining steel, it is readily available worldwide at a competitive price. --- ### **1. Chemical Composition (Standard Conformance)** The chemistry is precisely calibrated to achieve optimal chip-breaking characteristics while maintaining manufacturability. | Element | Standard Range (%) | Key Function | | :--- | :--- | :--- | | **Carbon (C)** | ≤ 0.13 (max) | Kept very low to ensure good ductility and prevent work hardening during machining. | | **Manganese (Mn)** | 0.70 – 1.00 | Combines with sulfur to form **manganese sulfide (MnS) inclusions**, which are the fundamental chip-breaking mechanism. | | **Phosphorus (P)** | 0.07 – 0.12 | **Elevated.** Increases strength slightly and, crucially, promotes the brittleness of chips, causing them to break cleanly. | | **Sulfur (S)** | 0.16 – 0.23 | **Elevated.** The primary free-machining element. The higher sulfur content (vs. 1211) defines 1212's superior and more consistent chip-breaking action. | | **Iron (Fe)** | Balance | Base element. | **Key International Standard Equivalents:** * **UNS:** G12120 * **AISI/SAE:** 1212 * **ASTM:** A29 (Specification for Steel Bars, Carbon and Alloy, Hot-Wrought) * **DIN (Germany):** 9SMn28 / 1.0715 (Very similar, commonly accepted equivalent) * **EN (Europe):** 1.0715 * **JIS (Japan):** SUM22 (Similar free-machining grade) --- ### **2. Typical Physical & Mechanical Properties (Hot Rolled, As-Rolled Condition)** *Note: Mechanical properties are secondary for this grade. It is selected almost exclusively for its machinability.* | Property | Typical Value / Description | | :--- | :--- | | **Density** | 7.87 g/cm³ | | **Machinability Rating** | **100%** (This is the **defining standard**. All other steels are rated relative to AISI 1212). | | **Tensile Strength** | 390 – 500 MPa (57 – 73 ksi) | | **Yield Strength (0.2% Offset)** | 285 – 380 MPa (41 – 55 ksi) | | **Elongation (in 50mm)** | 15% – 25% *(Note: Highly anisotropic; longitudinal value shown, transverse ductility is very low)* | | **Brinell Hardness (HB)** | 135 – 175 | | **Surface Condition** | Standard hot-rolled finish with adherent mill scale. | --- ### **3. Product Applications** AISI 1212 hot rolled rounds are the quintessential material for high-volume, precision-machined components across virtually every manufacturing sector. * **Screw Machine Products:** The #1 choice for parts made on automatic screw machines and Swiss-type lathes—bushings, fittings, spacers, shafts, nuts, and complex small components. * **Fasteners:** Nuts, bolts, set screws, and other non-critical fasteners produced in massive quantities. * **Electrical and Plumbing Fittings:** Connectors, couplings, valve bodies, and conduit fittings. * **Automotive Non-Structural Parts:** Fuel system fittings, sensor housings, clip bases, and countless other under-hood and interior components. * **Appliance and Hardware Components:** Gears, pins, levers, and brackets for consumer goods. --- ### **4. Critical Considerations & Limitations** * **Very Poor Weldability:** **NOT RECOMMENDED FOR WELDING.** The high sulfur and phosphorus content make it **extremely susceptible to hot cracking** and severe embrittlement in the weld zone. Joining must be mechanical. * **Anisotropic and Low Ductility:** Mechanical properties are highly directional. **Transverse ductility and impact toughness are very poor** due to the stringers of MnS inclusions. It must not be used for parts subjected to significant stress across the grain direction or impact loading. * **Not for Heat Treatment or Forging:** Cannot be strengthened by heat treatment due to low carbon content. The inclusion structure makes it unsuitable for forging or severe cold forming. * **Low Strength:** Should **never** be used for primary structural, load-bearing, or safety-critical applications. * **Mill Scale:** The hot-rolled surface scale must be removed (by machining, pickling, or blasting) for most applications. * **Comparison to 1211:** AISI 1212 has a higher and more tightly controlled sulfur range (0.16-0.23% vs. 0.10-0.15%), which generally gives it more consistent and slightly better machinability, making it the more prevalent choice globally. **Disclaimer:** AISI 1212 is a specialized **machining steel**. Its use must be strictly limited to applications where its unparalleled machinability is the primary requirement, and its significant weaknesses in weldability, transverse ductility, and strength are fully accounted for in the design. -:- For detailed product information, please contact sales. -: AISI 1212 Steel, hot rolled, 19-38 mm round Specification Dimensions Size： Diameter 20-1000 mm Length <5004 mm Size:We can customized as required Standard： Per your request or drawing We can customized as required Properties（Theoretical） Chemical Composition -:- For detailed product information, please contact sales. -: AISI 1212 Steel, hot rolled, 19-38 mm round Properties -:- For detailed product information, please contact sales. -:

Applications of AISI 1212 Steel, hot rolled, 19-38 mm round -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI 1212 Steel, hot rolled, 19-38 mm round -:- For detailed product information, please contact sales. -:

Packing of AISI 1212 Steel, hot rolled, 19-38 mm round -:- For detailed product information, please contact sales. -: Standard Packing: -:- For detailed product information, please contact sales. -: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 1475 gallon liquid totes Special package is available on request. E FORUs’ is carefully handled to minimize damage during storage and transportation and to preserve the quality of our products in their original condition