(一)前言钢板弹簧是汽车上比较重要总成之一。一般在动裁荷条件下工作,要求有较高的弯曲疲劳强度和良好的工艺性能,因此要求钢板弹簧材料具备高的抗拉强度、塑性、韧性;同时又要有一定的淬透性、低的脱炭敏感性、低的石墨化倾向;在热状态下容易弯曲成型和合适的热轧硬度便于剪切与冲孔。目前国内外汽车钢板弹簧大多采用硅一锰钢, (A) Preface Leaf spring is one of the more important assembly on the car. Generally work under dynamic load conditions, require a higher flexural fatigue strength and good process performance, thus requiring steel spring material with high tensile strength, plasticity, toughness; but also have a certain degree of hardenability, low Of the decarbonization sensitivity, low tendency of graphitization; easy to bend in hot forming and suitable hot-rolled hardness to facilitate cutting and punching. At present, most domestic automobile leaf springs use silicon-manganese steel,