Showing papers on "Peening published in 1980"

Modification of evaporated chromium by concurrent ion bombardment

Abstract: Bombardment of thermally evaporated chromium films with energetic inert gas ions during deposition (ion peening) causes marked changes in properties when the dose exceeds a minimum critical value. The property changes are characterized by a sharp reversal of intrinsic stress from high‐tensile to high‐compressive values, increases in the optical reflectance and optical density to levels approaching pure bulk chromium, and enhanced resistance to oxidation on heating. Observations of the shift in critical ion dose with accelerating voltage and ionic mass (argon and xenon) indicate that the ion peening transition may be controlled by the transfer of momentum to the depositing film. This observation is found to be consistent with results obtained in low‐pressure, cylindrical post‐magnetron sputtering, which ion peening was devised to simulate.

Leaf spring stress peening method and apparatus

Abstract: A leaf spring stress peening apparatus is composed of a first conveyor capable of transporting a plurality of leaf springs in an unstressed position. A second endless conveyor is provided to transport a plurality of leaf spring deflecting elements. The first and second conveyors are positioned so that the leaf springs on the first conveyor are deflected by the elements on the second conveyor in a shot peening area. A blast wheel is located in the shot peening area and is positioned to concentrate shot peening material on the side of the deflected spring which is in tension. The deflecting elements disengage the spring as it leaves the shot peening area.

Corrosion preventive piece joining method of turbine blade

Abstract: PURPOSE:To prevent stress corrosion cracking without having to form each member in special shape or making special treatment, by providing stress buffer part in the anticorrosive piece starting end part CONSTITUTION:A corrosion resistant member 2 is welded, by electron beam or the like, to a turbine blade part 1 which may be corroded by water drops in the working vapor, through an intermediate medium metal 3 The position starting shield by an anticorrosive piece 2 is built up by TIG welding, by using a metal which is more easily deformed plastically than the corrosive piece, for example, the same Inconel as the intermediate medium metal 3, as the filler metal, and a stress buffer part 6 is formed Next, with the main purpose of approaching the blade member welding heat affected zone to the property of the blade base metal, refining heat treatment is applied In this state, since the coefficient of thermal expansion of the anticorrosive piece is larger than that of other parts, tensile stress remains in the anticorrosive piece Hence, the stress buffer part is subjected to plastic deformation by peening, and, to the contrary, compressive stress is applied to the anticorrosive piece

Arc welding method of 13 chrome stainless steel

Abstract: PURPOSE:To prevent occurrence of intergranular corrosion stress corrosion crack in the weld zone under corrosive environment by welding the weld groove part provided in 13 Cr stainless steel with austenitic welding material, and then welding and laminating the surface layer part with specified welding material to eliminate color difference between the base metal and weld zone CONSTITUTION:Defect due to pitting corrosion occuring in a base metal 4 made of 13 Cr stainless steel is removed and a weld groove 5 is formed After preheating about to 250 degC, welding 6 is performed by using an austenitic welding rod, then the weld bead surface is peened in order to release of welding residual stress Further, this surface layer part is welded and laminated as shown by the shaded zone 7, by using a martensitic welding material containing Ni 13 Cr This method is particularly suited to perform local welding in applications where normal annealing treatment connot be made after welding

Enhancement of fatigue strength of gear

Abstract: PURPOSE:To greatly increase the fatigue strength of gears by a method in which a pressure applied through hard spheres on the inside-diameter wall of a gear so as to generate a tensile stress in the circumferential direction of the gear bottom, and under the condition, the gear is subjected to a shot peening. CONSTITUTION:Hard spheres 2 of steel, ceramic, etc., whose surfaces are coated with a lubricant are packed in the inside-diameter wall 1a of a cylindrical gear 1 through which a shaft is passed, and a tensile stress is applied to the circumferential direction of the outside diameter (gear bottom) of the gear through the spheres as pressure mediums. In short, a cover 7 for the periphery of a lower spacer 9 is vertically provided on a base 10, gears 1 are stacked up, and then the hard spheres 2 are packed. Then, a bolt 6 is inserted into the hole 3a of a piston 3, the small-diameter portion is set in such a way that it is positioned inside the hole 8a of the upper spacer 8, and then a pressure is applied by clamping it with nuts. Thus, a circumferential tensile stress is generated in the outside diameter (gear bottom) of the gears for stress peening.

Improving the fatigue performance of welded aluminum alloys

Abstract: Postweld brush shot peening improves the fatigue performance of butt-welded 5086-H116 (with the weld reinforcement removed) to the level of unwelded base metal and can increase the fatigue strength of 5086-H116 fillet welds from 5,500 to 10,000 psi at 10**7 cycles. The ability to conduct the peening operation in an aluminum ship structure makes brush peening an attractive method both in new construction and during repair.

Effect of Multiple Shot Peening/Cadmium Plating on High Strength Steel

Abstract: : This report covers the effect of multiple shot peening and cadmium plating operations on a high strength steel alloy used in landing gear applications. The basis for determining this effect was fatigue and stress corrosion tests in a high humidity environment.

Shot peening work

Abstract: PURPOSE:To improve resistance of peening shots to breakage and to give effective shot peening to articles that should not be pulluted with iron, by using shots of nickel base alloy CONSTITUTION:A metallic article that should not be polluted by iron is applied peening by using as shots nickel base alloy with Vickers Hardness Hv400 or more to have in the article hardness that corresponds to the hardness of the shots in the range from the metal surface to the depth of about 50mum, and at the same time the shots themselves are improved in their resistance to breakage

Brittleness restoration treatment method of alloy

Abstract: PURPOSE:To improve the safety and reliability of brittleness restoration treatment by adding plastic working treatment during or before or after the treatment at the time of heating the low-alloy-steel-made apparatus which has been used for a long time under high temperatures at which aging deposition occurs at the temperature higher than its service temperature to perform the brittleness restoration treatment. CONSTITUTION:In case a low-alloy-cast steel-made product of Cr-MO base or Cr-Mo-V base has been used for a long period of time at high temperatures of 400- 600 deg.C, the defects, such as cracks, of the material based on a kind of annealing brittleness are produced. In this case, the toughness of the material is restored by heating the same to 650-700 deg.C, and during this restoration heat treatment or before or after the heat treatment, plastic working treatment, such as peening, is applied to the material, whereby the voids in the surface layer are eliminated and the brittleness restoration is accomplished safely and surely through working down to a depth of 1mm or more.