Optimization of friction stir welding process for joining of aluminum to steel

铝钢连接搅拌摩擦焊工艺优化

• 批准号: RGPIN-2017-05127
• 负责人: StGeorges, Lyne
• 金额: $ 1.6万
• 依托单位: Université du Québec à Chicoutimi
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=710042
• 关键词: Optimization; friction; stir; welding; process

Background Friction stir welding (FSW) is a solid-state welding process, which can produce high quality welds of several materials difficult to weld. Due to the low energy input used, FSW creates high strength joints with reduced distortion. Being capable of handling variations inherent to high volume production, advantages of FSW also include improved process robustness and reduced production costs. FSW has rapidly gained acceptance for the manufacturing of lightweight structures. The rising demands for improved fuel economy have driven the efforts for the development of innovative aluminum products for transportation vehicles. However, the majority of the structures used in vehicle involve steel and the employment of lightweight materials in steel structures is of great interest. The use of the combination of steel and aluminum alloys has been increasing in fabrication and many efforts to weld steel to aluminum alloy have been invested. Problem statement Although the benefits of FSW to join aluminum to steel are clear, the applications of FSW to alloys with high melting temperature have been limited due to stringent demands on the tool. The FSW tool is exposed to severe stress and high temperatures particularly for the welding of hard alloys such as steels, which promotes tool degradation. For these alloys, the commercial application of FSW is limited by the high cost and short life of FSW tools. Wear has a huge influence on tool life of FSW of steel. Therefore, it is important to identify and understand the wear mechanisms present. Tool wear is influenced by many factors, which include the composition of the tool and the workpiece material, the nature of the welding operation, the welding conditions and machine setup and the tool geometry. Methodology proposal and expected results In FSW, only limited work has been done on tool wear mechanisms. The goal of the proposed project is to identify the primary wear modes of tools used to produce aluminum to steel FSW joints and to explain the mechanisms contributing to tool wear and failure. With the help of existing wear models, critical factors that influence the behavior of tool wear in FSW will be identified. This knowledge will be applied to optimize welding conditions and tool performance. The identification of dominant wear mechanisms for this type of dissimilar welding will have a significant impact on the Canadian industry, because of its potential for the automotive and other industrial sectors. For the automotive industry, replacing steel with aluminum will decrease the weight of vehicle resulting in reduced fuel consumption and greenhouse gas emissions.

背景 搅拌摩擦焊（FSW）是一种固态焊接工艺，可对多种难焊材料进行高质量焊接。 由于所使用的能量输入较低，FSW可产生高强度接头，同时减少变形。 由于能够处理大批量生产所固有的变化，FSW的优点还包括改进的工艺鲁棒性和降低的生产成本。搅拌摩擦焊在制造轻质结构方面迅速获得认可。对提高燃油经济性的需求不断增长，推动了为运输车辆开发创新铝产品的努力。然而，车辆中使用的大多数结构涉及钢，并且在钢结构中使用轻质材料具有极大的兴趣。钢和铝合金的组合的使用在制造中已经增加，并且已经投入了许多努力来将钢焊接到铝合金。 问题陈述 虽然FSW连接铝和钢的好处是显而易见的，但由于对工具的严格要求，FSW在高熔化温度合金中的应用受到限制。 FSW工具暴露于严重的应力和高温下，特别是对于诸如钢的硬质合金的焊接，这促进了工具退化。 对于这些合金，搅拌摩擦焊工具的高成本和短寿命限制了其商业应用。磨损对搅拌摩擦焊刀具寿命有很大影响。因此，重要的是要识别和理解存在的磨损机制。工具磨损受许多因素的影响，包括工具和工件材料的成分、焊接操作的性质、焊接条件和机器设置以及工具几何形状。 方法建议和预期成果 在搅拌摩擦焊中，只有有限的工作已经做的工具磨损机制。 该项目的目标是确定用于生产铝钢搅拌摩擦焊接接头的工具的主要磨损模式，并解释导致工具磨损和失效的机制。 在现有磨损模型的帮助下，将确定影响搅拌摩擦焊刀具磨损行为的关键因素。这些知识将用于优化焊接条件和工具性能。 识别这种类型的异种焊接的主要磨损机制将对加拿大工业产生重大影响，因为它对汽车和其他工业部门的潜力。 对于汽车行业，用铝代替钢将降低车辆的重量，从而减少燃料消耗和温室气体排放。