Analysis and characterization of microstructure, residual stress, and resultant in-service properties for production of inline-4 aluminum engine block

发动机重量的最小化通常依赖于使用轻合金，如铝和镁，而不是更重的合金，如铸铁或钢。然而，轻合金不像钢或铁那样具有显著的高温机械性能。因此，当在高温和高 ** 负荷下使用时，轻合金往往容易发生永久变形或断裂。这些材料 ** 失效可能导致燃烧室密封不当，导致空气-燃料 ** 混合物排放到大气中（称为漏气）。即使发生极少量的漏气，发动机效率也会急剧下降，从而导致燃油消耗增加和有害气体排放迅速增加。由此导致的召回将给汽车制造商带来重大经济损失。**因此，研究新福特发动机缸体中的铝和铁线如何相互作用，以优化制造工艺（铸造、热处理和机加工）是很重要的。这项研究的结果 ** 对于减少或消除发动机铸件中可能导致不希望的变形、** 低机械性能的缺陷，以及消除可能导致漏气或发动机在 ** 使用期间故障的材料开裂至关重要。本项目的目标包括：（i）正确确定和量化制造过程中的残余应力演变。这将使加拿大福特公司能够确定和调整可能导致高残余应力的制造 ** 工艺，这些残余应力会导致部件在使用过程中失效，以及（ii）** 研究铸铁内衬如何影响铝合金的局部微观结构。这将为 ** 福特提供有关材料在铸造过程中表现的关键信息（冷却速率、热膨胀系数 ** 不匹配、局部合金强度、微观结构等）。这项工作将提供有关如何 ** 制造工艺应进行优化，以提供更好的合金铸造后的机械性能和 ** 铸造后热处理的信息。最终，这项研究旨在为福特加拿大公司提供一种新的更轻的发动机缸体的材料和制造工艺，从而进一步提高燃油效率。

Minimization of engine weight often relies on the use of light alloys such as aluminum and magnesium, rather**than heavier alloys such as cast iron or steel. However, light alloys do not have as substantial elevated**temperature mechanical properties as do steel or iron. Therefore, while under elevated temperatures and high**loads during service, light alloys are often susceptible to permanent deformation or fracture. These material**failures may result in improper sealing of the combustion chamber, resulting in discharge of the air-fuel**mixture to the atmosphere, (known as blow-by). Even with minute amounts of blow-by occurring, the engine**efficiency drastically decreases, which results in increased fuel consumption and a rapid increase in hazardous**emissions. The resulted recalls would lead to significant financial losses for the automotive manufacture.**Therefore, it is important to study how the aluminum and iron lines interact in the new Ford engine blocks to**be able to optimize the manufacturing process (casting, heat treatment and machining). The results of this study**are critical to reduce or eliminate defects in the engine casting that may contribute to undesirable distortion,**low mechanical properties, and eliminate material cracking that may lead to blow-by or engine failure during**service. The objectives of this project include: (i) proper determination and quantification of the residual**stresses evolution during manufacturing. This will allow Ford Canada to identify and adjust the manufacturing**processes that may lead to high residual stresses, which contribute to component failure during service, and (ii)**to study how cast-in iron liners influence the local microstructure of the aluminum alloy. This will provide**Ford with critical information on how the material behaves during casting (cooling rates, coefficient of thermal**expansion mismatch, local alloy strength, microstructure, etc.). This work will provide information on how the**manufacturing process should be optimized to provide better alloy mechanical properties after casting and**post-casting heat treatment. Ultimately, this research looks to provide Ford Canada with a material and**manufacturing process for a new lighter engine block, enabling further increase in fuel efficiency.