Search Results for solution treatment

All superalloys, whether precipitation hardened or not, are heated at some point in their production for a subsequent processing step or, as needed, to alter their microstructure. This chapter discusses the changes that occur in superalloys during heat treatment and the many reasons such changes are required. It describes several types of treatments, including stress relieving, in-process annealing, full annealing, solution annealing, coating diffusion, and precipitation hardening. It discusses the temperatures, holding times, and heating and cooling rates necessary to achieve the desired objectives of quenching, annealing, and aging along with the associated risks of surface damage caused by oxidation, carbon pickup, alloy depletion, intergranular attack, and environmental contaminants. It also discusses heat treatment atmospheres, furnace and fixturing requirements, and practical considerations, including heating and cooling rates for wrought and cast superalloys and combined treatments such as solution annealing and vacuum brazing.

Titanium castings are used in a wide range of aerospace, chemical process, marine, biomedical, and automotive applications. This chapter provides an overview of titanium casting and associated processes and how they compare with other manufacturing methods. It also discusses the role heat treating and its effect on the tensile properties of different titanium alloys.

This chapter discusses the effect of heat treating on titanium alloys and the influence of time and temperature on critical properties and behaviors. It explains how heat treatments are used to make titanium stronger, tougher, more ductile, and easier to machine as well as more resistant to the effects of corrosion and thermal and mechanical fatigue. It describes accepted practices for stress relieving, aging, annealing, and post-treatment processing along with associated challenges and concerns.

Titanium alloys respond well to heat treatment be it to increase strength (age hardening), reduce residual stresses, or minimize tradeoffs in ductility, machinability, and dimensional and structural stability (annealing). This chapter describes the phase transformations associated with these processes, explaining how and why they occur and how they are typically controlled. It makes extensive use of phase diagrams and cooling curves to illustrate the effects of alloying and quenching on beta-to-alpha transformations and the conditions that produce metastable phases. It also examines several time-temperature-transformation diagrams, which account for the effect of cooling rate.

Nonferrous alloys are heat treated for a variety of reasons. Heat treating can reduce internal stresses, redistribute alloying elements, promote grain formation and growth, produce new phases, and alter surface chemistry. This chapter describes heat treatment processes and how nonferrous alloys respond to them. It provides information on aluminum, cobalt, copper, magnesium, nickel, and titanium alloys and their composition, microstructure, properties, and processing characteristics.