This book is designed to provide engineers with a better understanding of heat treatment and its effects on gear quality and performance, especially as these considerations are critical to ensuring that the. Heat treatment in order to use khk stock gears safely, carefully read the application hints before proceeding. Gears play an essential role in the performance of many products that we rely on in our everyday lives. The heat treating of gears is a critical aspect of gear production.
Risk management in heat treatment 10 investment castings can have significant decarburization stemming from subpar conditions in foundry equipment, but this can be reversed during heat. This article provides an overview of steel gear heat treating processes and brings out the nuances of the various important heat treating considerations for steel gear applications. Perform preparation to product and equipment for heat treatment in an efficient and safe manner. Typical heat treatment defects of gears and solutions. The focus of this article will be on heat treatment of gears intended for heavy duty service applications. Selection of material and compatible heat treatments for. To understand why heat treating is important we look to the model of material science figure 1. The materials herein described are generally used in japan. The important heat treating processes during gear manufacturing include preparation treat ments before machining or hardening, and hardening treatments.
Gear hardening and tempering heat treating with the. Heat treatment and quenching of gears is a complex process. It is the purpose of this article to examine the causes of. Manufacturing of gears presents a demanding challenge for metallurgists in. The fatigue strength values of case hardened and quenched and. Gears play an essential role in the performance of the prod ucts that we rely on. Automotive gears represent another important category of components that are heavily stressed and require high levels of performance in the areas of both fatigue and wear resistance. Sae aisi 4140 steel properties, material heat treatment.
Using the thermal boundary conditions predicted by cfd models, heat treatment simulations have been developed to predict the component response during. The processes of carburizing for surface hardening, quenching for through hardness, and cryotreating for. Heat treatment processes in gear design prepared by. Heat treat processes for gears gear solutions magazine. If there are questions or if you require clarifications, please contact our technical. Its contribution is vitally important for cost control. Heat treatment of steel gears heat treating of irons and. Made the gears on a horizontal mill with index head. Heat treatment of gears is designed to provide the gear design engineer with a better understanding of heat treatment and its effects on gear quality and performance, especially as these considerations are. Heat treatment makes a metal more useful by making it stronger and more resistant to impact, or alternatively, making it more malleable and ductile. Selecting the best carburizing method for the heat treatment of gears daniel h. Effect of quenchant flow on the distortion of carburized. Heat treat processes for gears gear solutions magazine your.
Gear heat treatment can be done in a wide variety of different types of industrial furnaces, each with its own unique. The influence of materials and geometry types of gears gears play an essential role in the performance of the products that we rely on in our everyday lives. Cogmatic uses a spin induction heat treatment process to provide a case hardness for customer parts. Variety of furnaces can be used for heat treatment of gears. When we think about gears we generally separate them into two categories motion. Vacuum carburizing has proven itself a robust heat treatment process and a viable alternative to atmosphere carburizing. Scm440 has more strength than s45c and is used with thermalrefining or inductionhardening treatment for producing gears. S45c ssay spur gears m1 page 124 series ssa spur gears m1 5.
Over the last 50 years, a great deal of research has been carried out and published in the disciplines. Recognize how the various heat treatment processes apply to the relevant agma documents. However, parallel axes spur and helical gears are the main gears in automotive transmission. One is a process of heat treatment and other is a extrinsic property of a material. Crmrmo carburizing steel are carburized using acetylene gas at. Heat treatment unit 5 21 hardening and hardness are two very different things. This heat treating process is localized to the entire tooth profile where case hardness. Lynn ferguson steel gears are heat treated to obtain enhanced properties and improved service. Induction hardening2 is applied after thermal refining.
Heat treating heavyduty gears gear solutions magazine. Improvements in dimensional control of heat treated gears. Previous processing variables, as well as the heat treatment parameters of time, temperature, agitation, and quenchant must be carefully. Gear materials and heat treatments it is essential to select proper materials and heat treatments in accordance with the intended application of the gear. However, distortion of the gear after heat treatment offers the engineer a challenging opportunity not only in ensuring a high quality product but also in controlling manufacturing costs.
Heat treat distortion of gears is discussed in detail for the major heat treat process, and a case history of each successful gear heat treat process is included. Selecting the best carburizing method for the heat. Annotation rakhit wants other engineers to avoid the considerable trouble he had understanding the art of gear heat treatment when he first embarked on a career in gear design and manufacturing. Heat treatment process an overview sciencedirect topics. The exploration of some definitions of heat treating processes from. Heat treatment is a critical and complex element in the manufacturing of gears that greatly impacts how each will perform in. Typical heat treatment defects of gears and solutions using fea modeling by zhichao li and b. Heat treatment of landinggear alloys historically, the heat treatment of landing gear has been done in lar ge gantrytype atmosphere furnaces fig. Heat treatment equipment operator education american. Sae 4140 aisi 4140 steel is a crmo series chrome molybdenum series low alloy steel, this material has high strength and hardenability, good toughness, small deformation. Pdf heat treating and quenching are arguably the most critical operations in the manufacture of gears. Heat treatment is a critical and complex element in the manufacturing of gears that greatly impacts how each will perform in transmitting power or carrying motion to other components in an assembly. Lindell metal improvement company, inc twin disc, inc. The thermochemical heat treatment processes, carburizing and nitriding, enhance excellently the fatigue strength of components of steel.
1650 1553 1095 89 436 1449 19 1114 471 1039 430 665 97 409 862 982 720 284 973 194 649 68 1451 1262 579 273 1325 1457 1220 203 1568 1336 776 1167 735 457 395 889 1451 782 319 1308 333 339 1079 217 370