Abstract: An improved sheet steel suitable for the production of containers and the like has a thin composite coating of nickel and zinc plated on both sides thereof. The steel substrate may be flat rolled blackplate and the composite nickel-zinc coating may be plated thereon by drawing a running length or strip of the steel through a nickel electroplating bath to which has been added the necessary concentration of zinc, and electrodepositing the two coating metals simultaneously and in the desired proportions. The coated steel sheet is particularly useful in forming drawn and ironed cans although it may be used for other purposes.

Abstract: An electrical resistant alloy for use in a sensing coil having a small temperature dependence of electric resistance over a wide temperature range and a method of producing the same are disclosed. This alloy consists of 55.5 to 60.6 wt % of palladium and 44.5 to 39.4 wt % of silver and an inevitable amount of impurities, and has a temperature coefficient of electric resistance of .+-.20.times.10.sup.-6 /.degree.C. over a temperature range of -50.degree. C. to +730.degree. C.

Abstract: A process for producing grain oriented electromagnetic silicon steel. The process includes the steps of: preparing a melt of silicon steel having, by weight, from 2.5 to 4.0% silicon; casting the steel; hot rolling the steel; cold rolling the steel; decarburizing the steel; applying a substantially non-reactive aluminum hydroxide coating to the steel; and final texture annealing the steel. The annealed steel being characterized by a substantially uniform metallic surface.

Abstract: The surface of a metal from the group of molybdenum, nickel, iron, tungsten and copper, or an alloy comprising at least one metal from this group, is made thermally black (black for thermal radiation) and very resistant to high temperatures. This is achieved by coating the metal or alloy with a layer of aluminum which is from one to a few .mu.m thick. The metal or the alloy thus coated is then heated in a nonreactive atmosphere until the aluminum has reacted with the metal or a metal from the alloy. Finally, the coated metal or alloy is fired in wet hydrogen so that the aluminum is partially oxidized from the compound of the aluminum with the metal or the alloy. In this manner a thermally black surface which can withstand very high temperatures is obtained.

Abstract: A process of providing electromagnetic steel strips or sheet with excellent magnetic properties. The process comprises the steps of:irradiating with a laser-beam the surface of an electromagnetic steel sheet which has been finally annealed, thereby locally forming marks of the laser-beam irradiation on the surface of the steel, and;subsequently, subjecting the steel sheet to the formation of an insulating film on the sheet surface at a temperature of the sheet not exceeding 600.degree. C.

Abstract: Disclosed are processes and articles for composite electroless coatings comprising at least two distinct layers, the first layer comprising a metal and/or a metal alloy plus particulate matter and the second layer comprising a metal and/or a metal alloy and being substantially free of particulate matter.

Abstract: Disclosed are processes and articles for composite electroless coatings comprising at least two distinct layers, the first layer comprising a metal and/or a metal alloy plus particulate matter and the second layer comprising a metal and/or a metal alloy and being substantially free of particulate matter.

Abstract: A method for inhibiting corrosion of a metal surface is disclosed. The method comprises contacting said metal surface with a corrosion inhibitor of the formula ##STR1## wherein R is selected from the group consisting of aliphatic radicals containing from about 6 to about 22 carbon atoms, R.sub.1 --C.sub.m H.sub.2m -- wherein R.sub.1 is alkoxy containing from 6 to 22 carbon atoms and m is an integer of from 2 to 6, and ##STR2## wherein R.sub.2 is alkyl containing from 1 to 20 carbon atoms, x is an integer of from 1 to 10 and each R.sub.3 is independently hydrogen or methyl; and R' is selected from the group consisting of hydrogen, C.sub.1 -C.sub.12 alkyl, and C.sub.1 -C.sub.12 alkoxy, at a temperature and for a period of time sufficient to inhibit corrosion of said metal surface.A method for pretreating a metal surface to improve the adhesion of paint thereto is disclosed.

Abstract: A process for improving the wear resistance of metals, comprising the operation of implanting into a metal article the wear resistance of which is to be improved ions of a material which is capable of forming within the article oxide compounds having a perovskite-type structure, and terminating the implantation of the ions when a dose of at least 10.sup.15 ions per square centimeter has been implanted.The process may also include an oxidizing stage after the implantation of the ions. Examples of the process are described in which the article is made of a steel and the ions are selected from the group consisting of Y.sup.+, Sc.sup.+, Yb.sup.+, Ce.sup.+, La.sup.+ and Dy.sup.+.

Abstract: This invention relates to an aluminum-zinc alloy coated ferrous base product which exhibits improved atmospheric corrosion resistance, and to the process whereby such improved corrosion resistance may be realized. The process is characterized by the steps of heating such coated product to a temperature within the single phase region for the composition corresponding to the aluminum and zinc of said coating, defined as .alpha. in the FIGURE in the accompanying drawing, preferably at a temperature between about 650.degree. F. (343.degree. C.) to 750.degree. F. (399.degree. C.), for a period of time to solution treat the aluminum-zinc alloy coating overlay, and cooling slowly to at least 350.degree. F. (177.degree. C.).

Abstract: This invention relates to an aluminum-zinc alloy coated ferrous product whose coating is highly ductile, and to the method whereby such improved coating ductility may be realized. The process is characterized by the steps of thermally treating the aluminum-zinc alloy coated product by heating to a temperature between about 200.degree. F. (93.degree. C.) and 800.degree. F. (427.degree. C.) and holding for a period of time to effect metallurgical structure changes, among them being the precipitation of a second phase incoherent with the matrix, followed by slow cooling to at least 400.degree. F. (205.degree. C.). The resulting product is characterized by an aluminum-zinc alloy coating with a hardness no greater than about 115 VHN, and preferably no greater than about 110 VHN.

Abstract: A shaping ferrous metal member used in a metal-working apparatus is heat-treated at about 1,000.degree. C. for several hours in an incompletely burning fuel gas, to provide a burned gas atmosphere composed of 0.5 to 5.0% of CO, 8 to 12% of CO.sub.2, 0 to 0.5% of O.sub.2. A tough iron oxide layer of high quality is tightly deposited with a uniform thickness by said heat-treatment on the surface of shaping metal member which is abrasively contacted by a sliding semifinished metal product. The advantageous effect of this method is that a consumable shaping metal member has a life 2 to 4 times longer than that of a metal member which is conventionally heat-treated in a completely-burning fuel gas.

Abstract: A magnetic recording medium is produced by forming an alkaline aqueous slurry of an acicular hydrated iron oxide or an acicular iron oxide as a starting material; adding a water soluble silicate to said slurry; treating it by a hydrothermal reaction in a closed reactor as an autoclave at elevated temperature and pressure; dehydrating and drying said slurry to obtain a dry iron oxide containing SiO.sub.2 component; converting it into a magnetic metallic iron powder by a reduction in a reducing atmosphere as hydrogen atmosphere; and coating a magnetic composition obtained by mixing said magnetic metallic iron powder with a binder.

Abstract: Silicon-iron sheet products having good magnetic properties can be produced from low nitrogen alloy sheet material by heating in a nitrogen-bearing hydrogen atmosphere to a temperature sufficient to effect secondary recrystallization and thereafter heating to a higher temperature in a hydrogen atmosphere to effect removal of residual carbon, nitrogen, and sulfur.

Abstract: A process for producing electromagnetic silicon steel having a cube-on-edge orientation and a permeability of at least 1800 (G/O.sub.e) at 10 oersteds. The process includes the steps of preparing a melt of silicon steel containing from 0.02% to 0.06% carbon, from 0.0006% to 0.008% boron, up to 0.01% nitrogen, up to 0.008% aluminum and from 2.5% to 4.0% silicon, casting the steel, hot rolling the steel to hot band gage, annealing the hot band in a temperature range of from 1450.degree.-1650.degree. F., cold rolling the steel to a final gage of about 0.018 inch in one cold reduction, decarburizing the steel, applying a refractory oxide base coating to the steel and texture annealing the steel.

Abstract: An oxidation resistant ferritic steel alloy composition is disclosed consisting essentially of up to 0.05 carbon, 0.1-2% silicon, 2-8% aluminum, 0.02-1.0% yttrium, the balance being substantially iron and normal impurities.

Abstract: In the preferred embodiment, a method is disclosed for preparing a metal foil composed of a ferritic stainless steel alloy and having a surface that is substantially covered by high aspect alumina whiskers. The preferred foil alloy comprises 15 to 25 weight percent Cr, 3 to 6 weight percent Al, 0.3 to 1.0 weight percent Y and the balance Fe. The method comprises forming the foil by a metal peeling process and treating the foil by heating in air at a temperature between about 870.degree. C. and about 930.degree. C. for a time sufficient to grow the alumina whiskers. In a particularly useful embodiment, the whisker-covered foil is coated with a noble metal-impregnated alumina layer and wound into a suitable cylindrical structure for use as a monolith-type catalytic converter for automotive exhaust gas treatment.

Abstract: This invention relates to a resistive or semiconducting coating for use on current conductors in cryogenic applications. This includes copper-clad superconductor wire, copper wire used for stabilizing superconductor magnets, and for hyperconductors. The coating is a film of cuprous sulfide (Cu.sub.2 S) that has been found not to degrade the properties of the conductors. It is very adherent to the respective conductors and satisfies the mechanical, thermal and electrical requirements of coatings for the conductors.

Abstract: A method of producing stock material wherein a steel base is provided with a layer of tin thereon, the tin-layered steel is then cold rolled and thereafter heated to a temperature above 250.degree. F. but below the melting point of tin; in a second method of producing stock material, the stock is heated above the melting point of tin; also included are methods of producing containers utilizing stock produced by each of said stock producing methods; further included is another method of producing containers wherein a steel base is provided with a layer of tin thereon, heated to a temperature between 250.degree. F. to below the melting point of tin, and thereafter formed into a seamless container.

Abstract: Material surfaces are provided which maintain their characteristic properties over long periods and which resist degradation by the environment in which they are utilized. The surfaces are formed by exposing a surface of atomically clean material to a gas or liquid which interacts with the clean surface to form a composition having the properties desired and which is stable against degradation in the environment of use. The process is useful, for example, to render metals or metal alloys, such as iron or iron alloys, stable against oxidation by air by exposing the atomically clean surface to an ultrapure nitrogen environment, prior to exposure to a degrading environment, such as air. A new oxidation-resistant iron surface composition also is provided which comprises body-centered iron structures including nitrogen atoms interstitially.

Abstract: In finish annealing process for a grain-oriented electrical steel strip or sheet, an improvement is disclosed which comprises coating the grain-oriented electrical steel strip or sheet with an annealing separator having a water content adjusted to not more than 10%, drying the coated strip or sheet, forming it into a strip coil, and finish annealing the strip coil within the inner cover of an annealing furnace while controlling the pressure of the gas atmosphere within the inner cover.

Abstract: A coated article and method for producing the coated article are described. The article is coated with a system which provides protection against oxidation and corrosion and which significantly reduces the substrate temperature. An MCrAlY layer is applied to the article to be protected and a columnar grain ceramic is applied by vapor deposition to the MCrAlY coated article. An alumina layer which exists between the MCrAlY layer and the columnar ceramic layer provides for the adherence of the columnar layer to the MCrAlY layer.

Abstract: A process for the production of cube-on-edge oriented silicon steel of high permeability which comprises varying the temperature of the initial anneal and the quench starting temperature of the hot rolled steel in accordance with the aluminum and nitrogen contents of the steel. The initial anneal temperature ranges from about 1040.degree. to 1175.degree. C. and the quench starting temperature from about 700.degree. to 1090.degree. C. Improved permeability and core loss values are obtained over relatively broad aluminum and nitrogen ranges, viz., 0.024% to 0.040% total aluminum and 0.0050% to 0.0090% nitrogen, by ladle analysis.

Abstract: Fine magnetic particles with high saturation magnetization (over 140 emu/g) as well as high stability against oxidation in air, are produced by a process which comprises the first stage of oxidizing the surfaces of metallic particles consisting mainly of iron in an atmosphere containing both H.sub.2 O and H.sub.2 gases at an oxidizing temperature below 900.degree. C., and the second stage of further oxidizing the surfaces of the particles produced at the first stage in an atmosphere containing O.sub.2 gas.

Abstract: A grain oriented magnetic steel sheet having excellent magnetic properties containing not more than 4.5% silicon, in which a <001> axis of individual grains coincides with a rolling direction of the steel sheet, a crystal plane parallel to the steel sheet surface is composed of a {h, k, o} plane which is rotated and dispersed about an axis in the rolling direction, and a tension ranging substantially from 350 to 1500 g/mm.sup.2 is given to the steel sheet in the rolling direction.

Abstract: A technique for processing thin tapes of soft magnetic amorphous metal alloys to reduce their magnetic hysteresis losses. The technique involves preliminarily forming such a tape into a core, heating the core, and then controllably cooling the core, the heating and cooling being conducted in an oxidizing atmosphere. Maintaining the core during processing in a suitable longitudinal or transverse (relative to the tape) magnetic field can also produce improved properties. Certain tape cores so processed have particular magnetic hysteresis loss characteristics never heretofore known.

Abstract: Disclosed is a NICRALY alloy containing nominally about 16% chromium, about 5.3% aluminum, about 0.02% yttrium and the balance essentially nickel, and heat treated in a manner to develop an essentially aluminum oxide surface. The NICRALY alloy is especially suited for use as components and support systems in kilns that are used in the firing steps in the manufacture of ceramic articles.

Abstract: An acidic aqueous zinc-containing coating solution containing about 0.08 to about 0.2 weight percent of zinc, about 0.8 to about 3 weight percent of phosphate, about 0.05 to about 0.35 weight percent of chlorate, about 0.001 to about 0.1 weight percent of nitrite, and a complex fluoride ion having the following concentration:0.4.gtoreq.y.gtoreq.0.63x-0.042wherein x is the concentration of the zinc in weight percent and y is the concentration of the complex fluoride ion in weight percent. The coating solution is useful for forming on metal surfaces zinc phosphate coatings that exhibit excellent alkali resistance, good adhesion to a paint film, and good corrosion resistance after painting when used as an undercoat for the cationic electrodeposition of a paint film.

Abstract: A process for obtaining sealed electric passages through an insulating body nvolves subjecting a titanium oxide ceramic forming a portion of the insulating body to a reduction process at selected places where the passages are desired. The reduction process involves baking the titanium oxide ceramic in a reducing atmosphere. According to some embodiments of the invention, more of the ceramic portion than is necessary is first subjected to the reduction process and those surface portions that are not intended to be conductive are treated to have metallic traces removed therefrom.

Abstract: It has been found that hydration of aluminum oxide surface coatings to aluminum hydroxide may be curtailed by the presence of corrosion inhibiting amounts of amino phosphonate compounds. Effective inhibitors, such as nitrilotris (methylene) triphosphonic acid, may be applied to aluminum substrates having aluminum oxide surfaces thereupon in concentrations of less than 50% by weight in aqueous solution, and suitably from 1 to about 500 ppm.

Abstract: The invention is concerned with providing substrates with coatings obtainable from sols, for example to protect the substrate (such as in nuclear reactors or hydrocarbon cracking plant) or to provide a carrier for catalytically active material.Hitherto, coatings obtained from sols have had a high porosity and high surface area so that they have not been entirely satisfactory for the above applications.In the invention, dense, low-porosity coatings are provided by contacting the substrate with a sol of refractory material (e.g. CeO.sub.2 or SiO.sub.2) convertible to a gel of density at least 40% of the theoretical density of the refractory material, and converting the sol to the gel. Optionally, the gel may be converted to a ceramic coating by firing.

Abstract: A can at least a part of which is made of an electrolytically chromated steel sheet, said steel sheet having such a surface that when it is degreased in acetone for 1 minute and analyzed by an Auger electron spectrometer at an incident electron accelerating voltage of 3 KeV, a modulation voltage of 3 V, a modulation frequency of 12 to 20 KHz and a degree of vacuum of at least 6.times.10.sup.-8 torr, the ratio of the peak-peak distance (O.sub.P-P) of KL.sub.2.3 L.sub.2.3 of oxygen to the base-peak distance (Cr.sub.B-P) of L.sub.3 M.sub.2.3 M.sub.4.5 of chromium in the resulting Auger electron spectrum satisfies the following relation:6.5.gtoreq.(O.sub.P-P)/(Cr.sub.B-P).gtoreq.1.5.

Abstract: A lift-out roll for conveying a float glass ribbon formed on a bath of molten metal having excellent corrosion resistance to molten tin and high oxidation resistance is provided. The roll is made of a heat-resistant cast steel consisting essentially of 0.01-2.0 wt. % of a rare earthmetal; 0.1-3.0 wt. % of Al; 0.2-0.45 wt. % of C.; up to 2.0 wt. % of Si; up to 2.0 wt. % of Si; up to 2 wt. % of Mn; up to 0.04 wt. % of P; up to 0.04 wt. % of S; 19-22 wt. % of Ni; 23-27 wt. % of Cr and the balance of Fe.

Abstract: A liquid composition useful for minimizing corrosion of aluminum surfaces comprising ethylene glycol or propylene glycol and fluoroaliphaticsulfonamidophosphonic acid or the salt thereof.

Abstract: The invention refers to new compositions for protecting steel surfaces from the oxidizing action of atmosphere.The essential components are: glucosides of pyrogallic and/or allagic acid of molecular weight between 270 and 1200; phosphoric acid, phosphates of bivalent transition metals such as Zn and Mn and nitrates of bivalent metals such as Zn and Mn.

Abstract: Diffusion coating a substrate metal with a different metal, such as aluminum and zinc, that is then chemically removed from the coated substrate, provides the residual metal with a very desirable catalytic surface. At least about a third of the removable metal can be dissolved out. Platinum wire screens activated in this way make effective exhaust catalysts for automotive engines. Chromium-rich coating for protective purposes can be applied on a superalloy, diffusion coating in a pack that in addition to the chromium to be diffused, also contains at least about 3% Ni.sub.3 Al. Also the formation of alpha-chromium is reduced when the pack diffusion is carried out in a retort effectively not over five inches in height. Pack aluminizing in the presence of chromium makes a very effective aluminum- and chromium-containing top coating over platinum plated or platinum coated nickel-base superalloys.

Abstract: This invention relates to an aluminum-zinc alloy coated ferrous product whose coating is highly ductile, and to the method whereby such improved coating ductility may be realized. The process is characterized by the steps of thermally treating the aluminum-zinc alloy coated product by heating to a temperature between about 200.degree. F. (93.degree. C.) and 800.degree. F. (427.degree. C.) and holding for a period of time to effect metallurgical structure changes, among them being the precipitation of a second phase incoherent with the matrix, followed by slow cooling to at least 400.degree. F. (205.degree. C.). The resulting product is characterized by an aluminum-zinc alloy coating with a hardness no greater than about 115 VHN, and preferably no greater than about 110 VHN.

Abstract: An improved process for the production of coated cemented carbide products is disclosed. A cemented carbide substrate is treated to form a metal carbide, nitride or carbonitride coating. During the last part of this treatment or subsequent thereto, a sulfur-and/or nitrogen-containing gas is added to the atmosphere to form a sulfide-and/or nitride - containing layer on the coating. Thereafter, a wear-resistant oxide (e.g., aluminum oxide) coating is applied to form the improved coated cemented carbide product.

Abstract: Fabrication techniques for making nickel boron stranded wire braze preforms are described. The techniques involve the provision of the wire material in a stranded form having a large surface to volume ratio. This general form consists of a plurality of fine wires, having the desired cross-sectional area, which may be twisted or braided to produce the preform.

Abstract: Method for producing a hard metal body having increased wear resistance, the body containing at least one of the binder metals iron, cobalt and nickel and at least one carbide of the elements titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum and tungsten, the body being produced by way of sintering and having a nitrogen containing surface, comprises subjecting a hard metal body containing the binder metal and carbide to a pressure between 2 bar and 5000 bar in a sintering autoclave at a high temperature and in a nitrogen containing atmosphere, after final sintering, to enrich the hard metal body with nitrogen and to form the nitrogen containing surface.

Abstract: This protective coating on a metal surface, especially for aircraft bodies nd the like, has, on a pickled metal surface which may be anodized in addition to being pickled, a bonding primer layer and a polyurethane primer layer, an intermediate layer which is easily dissolved and a top layer forming a finish coat on said intermediate layer which protects the primer layers when the top coat is removed for a new paint job.

Abstract: An acidic aqueous coating solution for forming a coating on an aluminum surface which is corrosion resistant and to which overlying coatings adhere excellently. The coating solution contains a zirconium and/or hafnium compound, a fluoride compound, and a polyhydroxy compound having no more than 7 carbon atoms. The coating solution is capable of forming on an aluminum surface a uniformly colorless and clear coating so that the coated surface has the appearance of the underlying metal surface, that is, the coating can be formed without changing the appearance of the metal surface. When coating a bright shiny aluminum surface, there can be produced a coated surface having a uniformly bright shiny appearance which is maintained even after the coated surface is subjected to boiling water. Such surface is capable of undergoing the "muffle test" to confirm the presence of the clear and colorless coating.

Abstract: This is a method for making a low alloy iron having desirable magnetic characteristics suitable for electrical applications such as transformer cores. The ingot alloy has a relatively high (more than 50 ppm) sulfur and relatively high manganese (0.01-0.15%) and thus can be prepared from commercially available materials without further purification. While the sulfur in such a manganese containing alloy is not removed during final annealing (due to generally less than about 950.degree. C. final annealing temperatures of the primary recrystallization process) the use of a tensile stress (at least 200 psi) inducing glass coating provides for very low losses. The material contains significant amounts of both sulfur and manganese. Both the sulfur and manganese contribute towards the meltability of the alloy and the manganese contributes towards the workability (especially for cool rolling) of the sulfur containing material.

Abstract: The spectrally selective solar surfaces have been produced after heating the austenitic stainless steel AISI 321 at a firing temperature of 843.degree. K. and for firing times ranging from 10 to 20 minutes. The heating was carried out in a constant temperature oven under normal atmospheric conditions. The optimum values of solar absorptance .alpha..sub.s and near-normal emittance .epsilon..sub.s were found to be .alpha..sub.s =0.92+0.02, .epsilon..sub.s =0.22.+-.0.02 respectively. The corresponding values for the unheated steel were 0.50.+-.0.02 and 0.22.+-.0.22. Severe temperature treatments like quenching in liquid nitrogen at 77.degree. K. produced no adverse visible affect on the quality of the selective surfaces. It shows that the thermal coatings so produced are very tough and durable. The value of solar absorptance and near-normal thermal emittance remained unchanged after quenching in liquod nitrogen.

Abstract: A coated cemented carbide article comprises a cemented carbide substrate, the surface regions thereof having diffused therein an element such as boron, silicon or aluminum. The article further comprises a coating disposed on the diffused substrate, the coating being a boride such as titanium boride, hafnium boride, zirconium boride or tantalum boride. In another embodiment the coated cemented article further includes an interlayer sandwiched between the diffused substrate and the boride coating, the interlayer being one or more layers formed from the carbides, nitrides or carbonitrides of elements from groups IVb and Vb of the Periodic Table of Elements, and combinations thereof.

Abstract: A method of nitriding ferrous alloys for improving the quality and integrity of the resultant case or hardened surface portion formed thereby, comprising the application of a specific combination of sequenced temperature and nitrogen conditions.

Abstract: A method of treating a part which contains titanium in its outer surface luding the steps of removing a portion of the natural oxide layer, placing the part in an enclosure, evacuating the enclosure, isolating the evacuated enclosure, and introducing oxygen in an amount ranging from 10.sup.-3 to 2.55 milligrams for each square centimeter of total outer part surface area, and heating to a temperature from 450.degree. C. to 880.degree. C.

Abstract: An alloy which is resistant to high temperature oxidation includes by weight 15 to 30% of chromium, at least 10% of nickel, at least 20% of iron, 4 to 6% of aluminum and at least 0.001% of at least one metal belonging to the group formed by the rare earths and metals in the same category, such as yttrium and scandium.

Abstract: In the process for preparing a magnetically stable, powder comprising the steps of reducing an iron oxide or iron oxide hydrate with a gaseous reduction agent and stabilizing the metallic powder thus produced, the improvement which comprises enhancing its reduction by coating said iron oxide or iron oxide hydrate with an antimony compound at a level of up to about 7 weight percent antimony based on the weight of the iron oxide prior to said reduction.

Abstract: Cold reduced, annealed steel strip and sheet stock having 0.2% yield strength of 45 to 65 ksi with an elongation of at least 25%, or having a yield strength of at least 90 ksi with an elongation of at least 10%. A low carbon steel (0.02-0.10% C) typical of rimmed or drawing steel analysis is preferably vacuum degassed, and 0.02% to 0.18% columbium is added. The casting is hot rolled, coiled not higher than 1300.degree. F., cold reduced 40% to 70%, and annealed at low temperature for a time sufficient to restore desired ductility without substantially decreasing yield strength.