The grain boundary structure is usually described by the coincidence site lattice (CSL) model based on the misorientation of adjoining crystals. Therefore, the objective of the present investigation is to seek the correlation between CSL fraction and creep resistance of modified 9Cr–1Mo steel (P91) with and without boron addition. Results showed that CSL fraction increases with increase in heat...

Cryogenics is the continuation of heat treatment and is the last step that completes the thermal treatment processing of metals. After ferrous steel part/s are heat-treated and tempered, the part’s grain structure can be improved by subjecting the part to a deep cryogenic temperature (–320 °F) soak. The process involves taking the parts down from room temperature to –70 °F to –100 °F using dry ...

This investigation is concerned to evaluate the influence of heat treatment on mechanical behavior of AISI1040 steel; it is one of the grades of medium carbon steel of American standard containing 0.40% carbon in its composition. Specimen of quenched/hardened AISI1040 steel was tempered at temperature (650,450&250°C) for 60, 90&120 minutes to modify desired properties. The mechanical behavior, ...

A duplex microstructure consisting of allotriomorphic ferrite and austenite at ambient temperature, has been produced in a low–alloy steel, by a simple heat treatment which involves intercritical annealing followed by quenching. The tensile properties obtained are good, with a total elongation of some 28% at an ultimate tensile strength approaching 900MPa. The form of the stress versus strain c...

In order to investigate lattice defects of 18-8 stainless steel after solution, precipitation and resolution treatments, thin films prepared from bulk specimens after the heat treatments were examined by means of transmission electron microscopy. In addition, measurements of the internal friction, specific gravity and electrical resistivity as well as Huey corrosion tests were conducted. The ex...

Structural steels with very high strength levels are often referred to as ultrahigh-strength steels (UHSS). The usage of UHSS has been extensively studied in aerospace industries and offshore platforms. In this study, medium carbon low alloy steel (AMS6305) was thermomechanicaly treated to obtain an ultra-high strength bainitic steel for aircraft engine compressor disk. A novel themomechanical ...

Transient thermal field in laser surface hardening treatment of medium carbon steel was analyzed by employing both three-dimensional analytical model and finite element model. In finite element model the laser beam was considered as a moving plane heat flux to establish the temperature rise distribution in the work-piece, while in analytical model laser beam was considered as an internal heat s...

The effect of heat treatment at 850 o Con the microstructure and mechanical properties of SAE 1025 carbon steel has been studied. Annealing, normalizing and age-hardening heat-treatments at 850 o C were used for the experimental work. Hardness tests, tensile tests and metallography were carried out on the heat-treated and control samples. The results were further analyzed using the one-way ANOV...