Keevitatav

Keevitatav is Estonian for weldable and refers to the property of a material to be joined by welding without unacceptable loss of strength or durability under typical service conditions. Weldability depends on chemical composition, microstructure, heat input, and the welding process, and is assessed through testing and historical performance.

Key factors influencing weldability include carbon content and sulfur/phosphorus levels, as well as alloying elements such as chromium, nickel, and vanadium. Low-carbon steels are generally highly weldable, while high-carbon steels may require preheating, controlled cooling, and post-weld heat treatment. Aluminum alloys pose challenges due to oxide layers and different alloys’ responses to heat, whereas magnesium is more sensitive to distortion and cracking. Stainless steels vary: austenitic grades usually weld well, while ferritic and martensitic types can be more prone to cracking or sensitization if not properly managed.

Welding methods commonly used for weldable materials include arc welding (MIG, TIG, shielded metal arc welding) and other fusion processes, with filler materials selected to match the base metal and service conditions. Proper procedure design often involves controlling preheating, interpass temperatures, heat input, and post-weld heat treatment to minimize defects and preserve toughness.

Testing and standards support weldability assessments, including mechanical tests (bend, impact, hardness), nondestructive examinations, and crack sensitivity evaluations, in accordance with ISO, EN, AWS/CEN guidelines. While a material may be classified as weldable, achieving reliable welds relies on appropriate welding procedures, joint design, and quality control. In industry, keevitatav is a key specification in material data sheets and welding procedure specifications.