Status Report No. 2 on Department of Defense Refractory Metals Sheet-rolling Program

Status Report No. 2 on Department of Defense Refractory Metals Sheet-rolling Program
Author: H. R. Ogden
Publisher:
Total Pages: 54
Release: 1962
Genre: Heat resistant alloys
ISBN:

The Nb program is nearing completion of laboratory tory rolling studiory materials, *Heat resistant alloys, *Sheets, Niobium alloys, Molybdenum alloys, Tantalum alloys, Tungsten alloys, Titanium alloys, Zirconium alloys, Tungsten, Powder metallurgy, Electric arcs, Manufacturing methods, Mechanical proper ies, Forging, Heat treatment, Melting, Extrusion, Deformation, Hardness, Rolling mills, Processing. Identifiers: Floturning. The Nb program is nearing completion of laboratory tory rolling studies, and a single composition for larger scale rolling studies will be selected in the near future. In the Mo program, it has been shown that true hot forging of billets to sheet bar results in higher recrystallization temperatures of TZM and Mo-0.5Ti sheet than are obtained when normal forging temperatures are used. The Ta program is in the early stages of ingot production and primary breakdown fabrication of the Ta-30Nb-7.5V alloy. Three methods of fabricating W sheet are being investigated: rolling of powder-metallurgy billets, fabrication of arc-melted ingots, and floturning of cylindrical blanks. Properties obtained on both powdermetallurgy and arc-melted tungsten sheet compare very favorably. Evaluation of the formability of Mo-alloy sheet has been delayed until sheet is available from the production program. (Author).

Properties of Coated Refractory Metals

Properties of Coated Refractory Metals
Author: W. A. Gibeaut
Publisher:
Total Pages: 104
Release: 1964
Genre: Heat resistant alloys
ISBN:

This report summarizes the information generated since the middle of 1961 on the chemical, physical, and mechanical properties of refractory metals that are coated with oxidation-resistant coatings of advanced-experimental or commercial status. It is a supplement to DMIC Report 162, Coatings for the Protection of Refractory Metals from Oxidation, dated November 24, 1961. Recent data on specific silicide- and aluminide- type coatings for columbium, molybdenum, tantalum, and tungsten and their alloys reflect general advances in coating quality and performance, understanding of the behavior of coated systems, and more complete realization of the problems associated with the use of coated hardware.

Summary of the Seventh Meeting of the Refractory Composites Working Group

Summary of the Seventh Meeting of the Refractory Composites Working Group
Author: W. A. Gibeaut
Publisher:
Total Pages: 72
Release: 1963
Genre: Heat resistant alloys
ISBN:

This report summarizes information on refractory composites for use above 2500 F, as presented at the Seventh Meeting of the Refractory Composites Working Group, held March 12-14, 1963. Reports presented at the meeting were concerned with pro tective coatings, insulating ceramics, materials for rocket thrust chambers, dispersion strength ening of metals, joining of refractory materials, and testing techniques. Emphasis in the field of coatings for refractory metals has shifted from the rudiments of developing oxidation-resistant coatings to improvement and advanced evaluation of coatings to predict their utility for re-entry vehicles. (Author).

The Mechanical Properties of the 18 Per Cent Nickel Maraging Steels

The Mechanical Properties of the 18 Per Cent Nickel Maraging Steels
Author: J. E. Campbell
Publisher:
Total Pages: 136
Release: 1964
Genre: Maraging steel
ISBN:

Since the combination of tensile properties and toughness that can be obtained with the maraging steels is higher than can be achieved with other steels by simple heat treatments, there is considerable interest in using the maraging steels for critical components such as rocket motor cases, pressure vessels, and aircraft forgings. This report includes information on the tensile, compressive, shear, bearing, dynamic modulus, impact, bend, fatigue, creep, and rupture properties of the 18 per cent nickel maraging steels and on the effect of temperature on these properties. Data for the properties of sheet, bar, and forgings, as well as data illustrating the effect of cold rolling, variation in the heat treatment, and elevated-temperature exposure also are presented. Data on the effect of specimen orientation, which are also included, indicate that the ductility and toughness of specimens designed to evaluate the properties in the short transverse direction are somewhat lower than in the other directions. The high strength and toughness that can be obtained in the 18 per cent nickel maraging steels make them attractive for certain critical applications that require these properties. The fabrication characteristics, weldability, and simple heat treatment are other advantages of these steels. (Author).

Semiaustenitic Precipitation-hardenable Stainless Steels

Semiaustenitic Precipitation-hardenable Stainless Steels
Author: D. C. Ludwigson
Publisher:
Total Pages: 186
Release: 1961
Genre: Heat resistant alloys
ISBN:

The semiaustenitic precipitation-hardenable stainless steels remain austenitic on cooling rom a solution heat treatment at about 1950 F. In this form they are readily fabricable. Subsequent treatment at about 1400 or at about 1725 F depletes the austenite of Cr and C to the extent that martensite forms on cooling to room temperature or -100 F, respectively. Final hardening is effected by tempering, or aging, at 750 to 1100 F. The semiaustenitic precipitation-hardenable stainless steels may be obtained as transformed at the mill by cold rolling. In this condition they lack the good formability of solution-heat-treated material. However, the fabricator need only temper them to obtain very high strengths. These steels have a combination of good formability, high strength, and excellent corrosion resistance that is not easily matched by other materials.