The Age-Hardening of Duralumin

The development of wrought alloys of aluminum to which high strength and ductility can be imparted by heat treatment began with the work of Wilm and Claesser in Germany, 1905­-1911. During this time an alloy was developed which was later commercially produced in that country under the tradename of duralumin. The need for strong, light alloys for aircraft during the World War greatly hastened the development of duralumin.

A Preliminary Study of Montana Copper - Nickel Ore

Deposits of sulfides, containing nickel and copper with associated platineferous minerals occur in the Stillwater Igneous Complex. This is a group of unusual igneous rocks situated in Stillwater and Sweetgrass counties in Montana.

Magnesium - Tellurium by Powder Methods

Today considerable work is being done in the compressed metal powder field which is gradually ob­taining prominence as a valuable branch of metallurgy. The mass of data, however, has led to many different ideas on the results of sintering.

The Age Hardening of Silver with Copper-Silicide

The successful application of the phenomenon of pre­cipitation hardening to aluminum and copper has indicated the possibility of hardening all metals in the same way. The phenomenon of age hardening was discoveredin 1911, and since that time much research has been car­ried on in all parts of the world on various alloy sys­tems.

Some Preliminary Investiagtions of the Magnetic Permeabilities of Alloys of the Ferromagnetic Metals

The problem presented for this thesis was an investigation of the magnetic properties of the alloys produced by the methods of powder metallurgy. The question behind this was the correlation of the magnetic properties with the bonding properties and with the diffusion of the constituents.

An Experimental Investigation of the Age Hardening of Copper with Manganese Silicide

The subject of the thesis was based upon the theory of precipitation or age hardening of the copper by the compound formed by the Manganese and silicon present in the ternary Cu-Mn-Si alloy. The effect of the heat treat­ment to such an alloy was to be studied and the best aging time and temperature was to be determined.

Porosity and Oil Absorption Properties of Metal Compacts of Copper - Tin - Graphite

Powder metallurgy, the most recent innovation in met­allurgical process, is not a new art; although not until recently did it become a matter of general interest, this being due not only to the products formed but also to the possibilities of future developments. The manufacture and application of metal powders is now beginning to take a position as a recognized part of the science of metallurgy.

Age Hardening of Copper-Aluminum Alloy Castings

Age hardening occurs in alloys of the solid solution type containing a hardening constituent, be it metal or metallic compound, which is more soluble in the solvent phase at higher temperatures than at lower ones.

The Effects of Some Percentages of Nickel on the Annealing of Cartridge Brass

The most important element in the alloying of steels, has also been used quite extensively as a third constituent in copper-zinc alloys. The chief characteristics of nickel which make it desirable as an alloying element are its toughness, high strength, and resistance to corrosion.

Methods of Determining Porosity and Spatter Losses of Arc Welds

The original objective of this project was to determine the effect of varying current intensity and electrode coating composition upon the spatter losses and porosity of arc welds made by alternating current. This subject was suggested by the Welding Research Council of the Engineering Foundation, which is a clearing house for welding research in order to avoid du­plication of work.

An Investigation of Age-Hardening in a Commercial Copper-Beryllium Alloy

This investigation is concerned with the age-hardening process as exemplified by the aging of a commercial Cu-Be alloy and, in particular, with this pro­cess as determined by X-ray methods. The amount of infor­mation available on age-hardening of commercial alloys is scanty and what information there is, is inaccurate.

An Investigation of Silicon Impregnation of Low-Carbon Steels

A problem of metallurgy during the last part of the Nineteenth and the early Twentieth Century, and one that stood very near the front, was investigations of methods to produce a non-corrosive surface on iron and steel without affecting the physical properties of these base metals.

Aluminum - Bronze Compacts and their Possible Use as a Bearing Material

In the modern aspect of powder metallurgy, the first use of a sintering process was in making filaments for incandescent electric lamps.In the short while from the day of Edison to the pres­ent, the science of working with metal powders has advanced by leaps and bounds.

Optimum Electron Temperature and Density for Short-Wavelength Plasma-Lasing from Nickel-like ions

Soft X-ray lasing across a Ni-like plasma gain-medium requires optimum electron temperature and density for attaining to the Ni-like ion stage and for population inversion in the View the MathML source3d94d1(J=0)→3d94p1(J=1) laser transition. Various scaling laws, function of operating parameters, were compared with respect to their predictions for optimum temperatures and densities. It is shown that the widely adopted local thermodynamic equilibrium (LTE) model underestimates the optimum plasma-lasing conditions. On the other hand, non-LTE models, especially when complemented with dielectronic recombination, provided accurate prediction of the optimum plasma-lasing conditions. It is further shown that, for targets with Z equal or greater than the rare-earth elements (e.g. Sm), the optimum electron density for plasma-lasing is not accessible for pump-pulses at View the MathML sourceλ=1ω=1μm. This observation explains a fundamental difficulty in saturating the wavelength of plasma-based X-ray lasers below 6.8 nm, unless using 2ω2ω pumping.

Chemical element contents and accumulation rates in metalliferous sediments from DSDP Hole 34-319, Bauer Deep, Southeast Pacific

Marked variations in the chemical and mineralogical composition of sediments at Site 319 have occurred during the 15 My history of sedimentation at this site. The change in composition through time parallels the variability observed in surface sediments from various parts of the Nazca Plate and can be related to variations in the proportion of hydrothermal, hydrogenous, detrital and biogenous phases reaching this site at different times. Metal accumulation rates at Site 319 reach a maximum near the basement for most elements, suggesting a strong hydrothermal contribution during the early history of this site. The hydrothermal contribution decreased rapidly as Site 319 moved away from the spreading center, although a subtle increase in this source is detectable about the time spreading began on the East Pacific Rise. The most recent sedimentation exhibits a strong detritalhydrogenous influence. Post-depositional diagenesis of amorphous phases has converted them to ironrich smectite and well-crystallized goethite without significantly altering the bulk composition of the sediment.