Abstract 1045 carbon steel and 30CrMnSiNi2A high-strength low-alloy (HSLA) steel were joined successfully using inertia friction welding. The effects of the rotational speed on the microstructure and mechanical properties of the joints were investigated. With increasing rotational speed, the tensile strength first increased and then decreased. The weld samples with the highest tensile strength (713 MPa), largest elongation (15.3 %), and high impact toughness (28.8 J/cm2) were achieved at a rotational speed of 2200 rpm. Using a higher rotational speed (2800 rpm) increased the width of the heat-affected zone (HAZ) on the 1045 carbon steel side. Welding joints failed in the base metal and HAZ of the 1045 carbon steel for samples prepared at 2200 and 2800 rpm, respectively. The highest joint efficiency obtained was 97 %, while the lowest was 63 %. The hardness profiles also indicated that the weld joint had higher hardness than that of either of the two base metals. The highest hardness of the weld joint (581 HV) was observed for the 2200-rpm sample. The high strength and toughness of the weld joint were attributed to the phase transformation of lath martensite, bainite, ultrafine ferrite and cementite at the weld interface. Welding defects were observed in the 1000-rpm sample as the low heat input and inclusions at the weld interface caused incomplete metallurgical bonding, resulting in the fracture occurring at the weld seam.

中文翻译：

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高强低合金钢与中碳钢惯性摩擦焊接头组织及力学性能

摘要 1045碳钢与30CrMnSiNi2A高强度低合金钢采用惯性摩擦焊成功连接。研究了转速对接头显微组织和力学性能的影响。随着转速的增加，抗拉强度先增大后减小。具有最高拉伸强度 (713 MPa)、最大延伸率 (15.3%) 和高冲击韧性 (28.8 J/cm2) 的焊缝样品在 2200 rpm 的转速下获得。使用更高的转速 (2800 rpm) 会增加 1045 碳钢一侧的热影响区 (HAZ) 的宽度。对于分别在 2200 和 2800 rpm 下制备的样品，焊接接头在 1045 碳钢的母材和热影响区中失败。获得的最高接头效率为 97%，而最低为 63%。硬度分布还表明，焊接接头的硬度高于两种母材中的任何一种。对于 2200 rpm 的样品，观察到焊接接头的最高硬度 (581 HV)。焊接接头的高强度和韧性归因于焊接界面处板条马氏体、贝氏体、超细铁素体和渗碳体的相变。在 1000 rpm 的样品中观察到焊接缺陷，因为焊缝界面处的低热量输入和夹杂物导致冶金结合不完全，导致焊缝处发生断裂。焊接接头的高强度和韧性归因于焊接界面处板条马氏体、贝氏体、超细铁素体和渗碳体的相变。在 1000 rpm 的样品中观察到焊接缺陷，因为焊缝界面处的低热量输入和夹杂物导致冶金结合不完全，导致焊缝处发生断裂。焊接接头的高强度和韧性归因于焊接界面处板条马氏体、贝氏体、超细铁素体和渗碳体的相变。在 1000 rpm 的样品中观察到焊接缺陷，因为焊缝界面处的低热量输入和夹杂物导致冶金结合不完全，导致焊缝处发生断裂。