Effect of Heat Treatment and Deformation on the Grain Size and Mechanical Properties of Duralumin-Type Alloys

Mechanical properties and the grain size of alloy D16ch and 1163 used for the sheeting of aircraft fuselages after 21% and 74% deformation and different kinds of heat treatment are studied. The effect of the modes of intermediate, preliminary, and final annealing operations on the grain size is determined. Recommendations are given for providing a small grain size.     

Alloying principles, phase transformations, structure and properties of low-temperature weldable shipbuilding steels

Basic principles for alloying low-temperature shipbuilding steels with yield strength ranging from 235 to 460 MPa are developed. Results of a study of phase transformations including strain-induced ones in the austenitic range are presented. Relations between structure and properties of low-temperature shipbuilding steels subjected to heat and thermomechanical treatment are determined. __________ Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 1, pp. 9–15, January, 2007.     

Interaction of zinc coating with aluminum and liquid metals

Metal Science and Heat Treatment -     

A computational fluid dynamic analysis of gas and particle flow in flame spraying

The flame spraying process, which is a common industrial thermal spraying application, has been analyzed by means of three-dimensional computational fluid dynamics (CFD) simulations. The process used at the Volvo Aero Corporation for the coating of fan and compressor housings has been modeled. The process uses the Metco 6P torch (Metco, Westbury, NY), which ejects a mixture of acetylene and oxygen at high speed through a ring of 16 orifices to form the flame. A stream of argon gas flowing through an orifice in the center of the ring carries a powder of nickel-covered bentonite through the flame to the spray substrate. The torch is cooled by a flow of air through an outer ring of 9 orifices. The simulation emulated reality closely by including the individual inlets for fuel, cooling air, and injected particles. The gas combustion was simulated as a turbulent, multicomponent chemically reacting flow. The standard, two-equation k-ε turbulence model was used. The chemical reaction rates appeared as source terms in the species transport equations. They were computed from the contributions of the Arrhenius rate expressions and the Magnussen and Hjertager eddy dissipation model. The first simulations included several intermediate chemical substances whose predicted concentration agreed favorably with measurements. Later, more simplified simulations incorporated only the global chemical reaction involving the initial and the final products, with corrections to the thermal properties being made to account for the missing intermediaries. The gas velocity and temperature fields predicted by the later simulations compared satisfactorily to those predicted by the earlier, more elaborate, ones. Therefore, the final simulations, which incorporated injected particles, were conducted employing the simplified model with only the global reaction. An in-house finite difference code was developed to calculate particle properties. Allowance was made for elliptical shapes, phase changes, and internal heat transfer with regard to the composite material. The particle velocities and temperatures predicted by the final simulations compared fairly well with experimental results obtained with the optical DPV2000 system.     

Effect of the Loading Rate on the Microhardness of Metallic Materials and the Micromechanism of Plastic Strain

Metal Science and Heat Treatment -     

Thermal Transformation of Transition Aluminas

JOM - This paper records conventional (CTEM) and scanning (STEM) microstructural examination of four transition aluminas (γ, δ, χ and κ) prepared from beohmite and...     

Structure and Properties of Amorphous-Crystalline Alloys of the Nd – Fe – B System

A novel x-ray technology is used for studying the phase composition and the sizes of crystallites in amorphous-crystalline alloys of the Nd – Fe – B system obtained by the method of centrifugal sputtering for manufacturing permanent magnets.