低合金高强钢是在低碳钢中添加少量的铌和 / 或钛等合金元素，使碳、氮等元素形成碳化物、氮化物并在铁素体基体上 析出，从而提高钢的强度。这种钢具有良好的成形性能和较高的强度，主要用于汽车座椅、横梁等结构件。 High-strength low-alloy steel is low carbon steel added with a trace of alloy elements such as niobium and/or titanium, which will be allowed to form carbide and nitride with carbon and nitrogen. And these carbide and nitride can separate out of ferritic matrix to increase steel strength. With excellent formability and relatively high strength, HSLA is mainly used for manufacturing structural parts of automobiles such as chairs and cross beams.