Optimizing Heat Treat Processes Through State-of-the-Art Metal Cleaning Capabilities

Metal cleaning has the potential to make or break heat treat processes. However, many heat treat companies are struggling with common cleaning challenges, including residual contaminations leading to insufficient hardening/nitriding/brazing results; surface stains on the finished products; inconsistent cleaning process as well as high cleaning costs due to high consumption of cleaning agent. In addition, burned oil can cause increased maintenance costs of the equipment and contaminate the facilities. The decision for a cleaning agent or sustainable cleaning technology has become more and more important under the aspect of current legislative efforts by the Environmental Protection Agency (EPA) in the US. This paper discusses the underlying causes behind these challenges and explains key factors fundamental to ensuring high-quality metal cleaning in terms of consistency, reliability and sustainability. Furthermore, it will introduce legally compliant, state-of-the-art cleaning capabilities such as closed vacuum cleaning technology with solvent, also known as airless system, the combined (two-step-) process of solvent and water in one machine; as well as a simple one-process step with two solvent based media. The theoretical principles will be further illustrated through a joint study with HEMO GmbH (HEMO), a manufacturer of cleaning machines, on cleaning trials based on different metals and contaminations.

Organizing Committee and Reviewers

Listings of the conference organizing committees and reviewers for Heat Treat 2021.

Heat Treating of EV Transmissions

As consumers embrace Electric Vehicle (EV) technology, the automotive industry is moving quickly into replacing internal combustion engines (ICE) and traditional transmissions. The change to electrically driven vehicles offers new challenges to the gear manufacturing world, and most importantly new specifications to heat treat these gears - specifically quieter gear sets and higher torque ratings. Today’s EVs have a much lower tolerance for noise from the gear set to power the vehicle; therefore, this continues the need for even quieter and stronger gears. This technical presentation will illustrate the heat treat and distortion specifications for these new gears, along with answering the “why” of selecting low pressure vacuum carburizing (LPC) for new programs around the world.

Advanced Automation in the Heat Treat Industry

Over the last 20 years, automation and robotics have become standard in production centers all around the world. In contrast, heat treatment processes are still typically manual and employee task oriented. In this presentation, we will review the latest developments and integration processes to improve the tact time of furnaces and guarantee process stability load after load, part after part. We will expand on how to use robotics for automatically loading and unloading a variety of parts on fixtures, and how automation can be utilized for checking mechanical and dimensional property before and after heat treatment. In addition, we will discuss how recipes can be automatically uploaded and full reports generated with details such as compliance and tolerances.

Introducing a New Industrial 3D Carbon/Composite Material for Heat Treat Applications

This paper introduces a new cost-effective grade of Carbon/Composite (C/C) for the manufacture of heat-treating fixtures, that brings the toughness associated with alloy materials, but with all the advantages C/C fixtures are known for.

Changes in Residual Stress State During Quench and Temper of Vacuum Carburized Gear Steel

Vacuum carburizing of 9310 gear steel followed by austenitizing, oil quench, cryogenic treatment, and tempering is known to impact residual stress state of the steel. Residual stress magnitude and depth distribution can have adverse effects on part distortion during intermediary and finish machining steps. The present research provides residual stress measurement, microstructural, and mechanical property data for samples taken along a specific heat treat sequence. Test rings of AISI 9310 steel are subjected to a representative gear manufacturing sequence that includes normalizing, rough machining, vacuum carburizing to 0.03”, austenitizing, quench, cryo-treatment, temper, and finish machining. Characterization of a test ring and a metallurgical sample after each manufacturing step allows tracking of residual stress and microstructural changes along the sequence. The results presented here are particularly interesting because the highest compressive residual stresses appear after removal of copper masking, not after quench as expected. Data can be used for future ICME models of the heat treat and subsequent machining steps. Analytical methods include X-Ray Diffraction, optical and electron microscopies, mechanical testing, and hardness testing.

A Study on Residual Stresses on Autofrettaged LDPE Tubing Including the Bauschinger Effect and Strain Aging

This paper compares and discusses the change to the residual stresses and strains on four tubes of SA-723 Gr 1 Cl 2 (Timken HS 220) tubing material that were autofrettaged at different Overstrain ratios (20% and 40%). The four tubes were autofrettaged with strain gages to obtain actual OD strain. The effect on the residual stress and strain of the material is reviewed after a single autofrettage and after a low temperature heat treat followed by a second autofrettage. The low temperature heat treat was performed on two of the four tubes to create comparable data. Any strain aging effect from the low temperature heat treat is examined on the measured residual stress and strains. The effect and possible benefits of strain aging and re-autofrettage on tubes with different Overstrain ratios is discussed. To obtain the residual stress values in the tube wall after the autofrettage cycles, the sample tube pieces were tested by X-ray diffraction. The actual residual stresses after autofrettage were then compared with the calculated theoretical residual stresses including Bauschinger effect correction factors from ASME Section VIII Div. 3 KD-5. The residual stress and strain data between one and two rounds of autofrettage is also studied to see if the Bauschinger effect is present.

In situ recycling of particulate matter for a high-performance supercapacitor and oxygen evolution reaction

MOFs/grephene aerogel capture particulate matter and in situ heat treat for high-performance energy applications.

High Pressure Gas Quenching Evolution

Gas quenching has been involved in heat treating for many years. Over those years, the technology has been looked at by many who heat treat to be limited to single chamber furnaces, which would standardly be 2, 6, 10 and 12 bar systems with varying methods of introducing the gas through the load. High pressure gas quenching has evolved tremendously to produce quenching with gas to provide properly hardened carbon steels for many applications including most automotive transmission products today. We will show that the technology used in high pressure gas quenching has improved and how the amount and method of cooling has evolved. Along with using new steels with higher hardenability, we will look at the evolution of high pressure gas quenching in heat treating and the systems available today with data from different loads at various cooling rates.