Forgings traditionally undergo normalizing or iso-annealing processes to achieve consistent hardness within controlled bands and to improve machinability. The need for these heat treatments stems primarily from the uncontrolled cooling of forgings after trimming operations. This paper demonstrates that similar results can be achieved through controlled cooling rates after trimming, with only minor differences in specific properties. The microstructure obtained through controlled cooling is predominantly coarse-grained, consisting of pearlite and ferrite matrices, contributing to improved machinability. Notably, the controlled cooling process offers potential energy savings of approximately 20 kg of oil per metric ton of net forging weight, with corresponding reductions in CO₂ emissions of up to 250 kg per metric ton. Implementation requires a specially designed cooling tunnel to regulate cooling rates precisely. This paper details the mechanical properties achieved for a carburizing grade steel, discusses necessary refinements to steel specifications, and outlines the process controls required to replace conventional normalizing/iso-annealing with controlled cooling effectively. Additionally, the paper presents the established cycles and cooling rates that produce optimal results in production environments.

An intricacy of the heat treating process is that improperly heat treated parts are not easily discernible in form and appearance from properly heat treated parts. Robust process and product control is critical to ensure all parts meet product specifications. AIAG (Automotive Industry Action Group) CQI-9 Special Process: Heat Treat System Assessment (HTSA) becomes a critical resource to ensure standardized process controls and drive continuous improvement in the automotive heat treat supply chain at all tier levels. Also, current trends in engineering design have led to tighter product requirements. Suppliers that use the CQI-9 HTSA will meet these ever demanding engineering expectations and improve their global competitiveness. This paper will show the contribution of CQI-9 and other standard process controls have reduced heat treat product issues by approximately 60%. Three case studies are presented that demonstrate process control requirements in CQI-9 can eliminate or reduce the risk of shipping non-conforming product to the customer.

For optimal performance, industrial applications rely on steel and other materials with precisely engineered properties. When these materials undergo welding during construction or modification while in service, their properties can degrade, potentially compromising their functionality. On-site heat treatment represents a critical method for restoring desirable material properties, traditionally performed by technicians who carefully monitor heating and cooling processes. Thermal Technologies International implements these treatments in accordance with industry standards, utilizing proprietary heat treating power supplies complemented by heating coils and thermal blankets. While this fundamental process has remained essentially unchanged for decades, emerging technologies are now transforming conventional heat treatment methodologies, introducing significant innovations to this essential industrial practice.

The very nature of global sourcing means that components must carry clear and detailed specifications for material, heat treatment, and test methods. Qualified global heat treat facilities can achieve good control of not only the common features such as surface and gradient hardness, but also of microstructure, core hardness, residual stress, and other critical metallurgical parameters. This paper will discuss a new concept for material specifications and more detailed heat treatment specifications for the global marketplace.

Insufficient and missing information can lead to avoidable costs in heat treatment, arising both from failures and from the time-consuming process of acquiring information. The Quality Assurance in Heat Treatment research group of the Association for Heat Treatment and Materials Technology aims to raise awareness among all heat treatment contractors about the importance of exchanging necessary information. This goal will be achieved by first documenting the essential information and then explaining why information exchange is crucial. Three examples are provided to demonstrate the impact of information on product outcomes. To disseminate these explanations to the general public, a concept and the initial implementation of a knowledge system are introduced.