Showing papers on "Butt joint published in 1984"

Integrated circuit isolation

Abstract: An integrated circuit isolation technology wherein the nitride-sidewall methods of the prior art are improved by performing an undercut and backfill before the second nitride (the sidewall nitride which prevents encroachment) is added to the first nitride (which covers the moat areas). Thus, the butt joint between the two nitrides is made more secure, and localized bird's-beaking at the butt joint between the moat nitride and the sidewall nitride does not occur.

Dependence of Cu/Sn and Cu/60Sn40Pb Solder Joint Strength on Diffusion Controlled Growth of Cu3Sn and Cu6Sn5

Abstract: The growth of intermetallic compounds and the strength of Cu/ Sn and Cu/ 60Sn40Pb butt joints were studied as a function of isothermal aging The effects of single-crystal (100), (110), and (111) oriented copper on the growth rates of Cu3Sn and Cu6Sn5 intermetallic compounds are characterized and the influence of elevated temperature aging on the tensile strength of butt joints analyzed Substrate orientation appears to influence the growth rate Metallographic measurements showed that the intermetallic compounds grew at a rate proportional to the square root of time Tensile tests of aged butt joints revealed a more complex time dependence

Method of joining pipes

Abstract: A method of replacing a defective circumferential butt joint in a metal pipe is disclosed. An annular metal bridge ring, having a smaller wall thickness than the pipe but the same inside diameter, is positioned coaxial with the pipe in the relatively wide gap created by the removal of the defective joint. The ring becomes an integral part of the weld by being welded in place, thereby partially filling the gap between the edge surfaces of the pipe exposed by the removal of the defective joint. Subsequent layers of fusible material are weld deposited in place on top of the ring until the gap is filled to the exterior pipe surface. Use of the ring in the gap enables replacement of the defective joint with a single weld.

Evaluation of Adhesive Test Methods

Abstract: Three approaches to bond strength analysis are discussed in this article: those based upon linear elastic stresses, those based upon linear fracture mechanics parameters, and those based upon nonlinear analyses. The first two approaches are then discussed with respect to standard adhesion test methods. The stresses in linear lap shear test specimens are shown analytically and experimentally to be concentrated at the bond termination and to be strongly dependent upon adherend thickness for standard tests. The bond stress intensity factors and energy release rates near the bond termination are given and discussed. Adherend thickness should be at least 4 times larger than that recommended by standard test techniques. The stresses in butt tensile tests are also discussed. It is shown that test specimen alignment problems can lead to low debond forces and excessively large data scatter. Stress intensity factors are also determined for butt tensile tests.

Adhesive Tensile Strengths of Scarf and Butt Joints of Steel Plates : 1st Report, A Case of Brittle Adhesive

Abstract: Adhesive tensile strengths, o f scarf joints with various scar f angles and butt joints with various adhesive layer thicknesses have been measured to establish fracture criterion for joints of steel plates bonded by brittle epoxy adhesive. A three-dimensional elastic stress analysis of these joints was performed by FEM. Fractures of both joints were explained quantitatively by introducing a boundary layer depth of 0.035 mm at free surfaces of adhesive layers and obeying maximum principal stress criterion. In adhesive layers of scarf joints with 0.1 mm layer thickness, the boundary layer depth of 0.035 mm included most of stress concentrated area at free surfaces. Locations of fracture initiation and fracture modes of adhesive layers observed with an optical microscope and a scanning electron microscope agreed with those expected from stress distributions and boundary layer conception.

Improvement of impact fatigue strength of adhesive joint by CTBN modification

Abstract: Impact fatigue behaviors of the steel/CTBN-modified adhesive/steel butt joint were investigated. The adhesive butt joint specimens used in the present work were bonded with epoxy–polyamide and CTBN-modified epoxy–polyamide adhesives. Fatigue tests were also conducted under nonimpact stress conditions to compare with the results from the impact fatigue test. The experiments showed that for the joint specimen from the adhesive modified with the CTBN the fatigue strength becomes higher under both of the stress conditions. In particular, the fatigue strength was improved remarkably under impact stress condition, that is, the distinct stress cycles dependence of impact strength was decreased by modifying the adhesive with CTBN. Furthermore, the effect of adhesive thickness on the fatigue strength was also discussed for the adhesive joint modified with CTBN. Under impact stress conditions, the relation between the fatigue strength and the adhesive layer thickness is different from that under the nonimpact one.

Fatigue Behavior of Butt Welds with Slag Inclusions

Abstract: The results of an experimental study on the fatigue behavior of transverse welded steel butt joints containing slag inclusion discontinuities are presented. Twenty‐four constant amplitude zero‐to‐tension fatigue tests were conducted. The 5 in. (127 mm) wide by 1 in. (25 mm) thick quenched and tempered steel specimens were manually welded using the shielded metal arc process. The size, shape, location, and number of slag inclusions entrapped in the welds were varied to examine the relative importance of these factors on the fatigue behavior. The onset of fatigue crack initiation was estimated by monitoring strain gages on the weld surface near the entrapped slag and by examining records of the ultrasonic signal from the slag inclusions. The test results indicate that: (1) Approximately one‐fourth of the total fatgue life was spent in initiating a fatigue crack, and that nearly 55% of the fatigue life was required for propagation of a crack to the weld surface; (2) a number of fatigue cracks initiated at sm...

Sheet metal blank for use in the manufacture of rolled bushings for sliding surface bearings

Abstract: Rolled bushings for sliding surface bearings have a locked butt joint extending throughout the length of the bearing. The joint comprises a lug (7), which is provided on one of the edge portions forming the butt joint and is received by a notch (8) formed in the other of said edge portions. In order to avoid a waste of material on cutting the blank, the notch and lug have the same contour and the head of the lug has the configuration of a rectangle with rounded corners.

Articulated butt joint for suspended rails of a monorail suspended railway

Abstract: Articulated butt joint for suspended rails of a monorail suspended railway, wherein the connection between the lower flanges is deformable as to be horizontal and vertical transverse forces and wherein the connection between the upper flanges absorbs the horizontal and vertical transverse forces. The aim of the present invention is to provide a butt joint which is more appropriate to withstand the transverse forces generated by the vehicle weight and to further reduce to the minimum the inevitable impact forces upon overrunning the expansion gap, as well as their negative consequences. To this effect, the present invention proposes that the linking elements (5) between the upper flanges be comprised of suspension metal plates (10) secured to the upper flanges, overlapping each other in the longitudinal direction of the rails and provided in the overlapping area with longitudinal holes (11) covering each other and tapered as an arc of a circle and intended to receive a suspension bolt (12), the medial point (13) being located in the middle of the expansion gap and at the height of the rolling surfaces on the upper side of the lower flange.

Prestressed concrete or reinforced concrete bending support

Abstract: Prestressed concrete or reinforced concrete bending support, in particular concrete pole, consisting of at least two sections (1, 2) which are interconnected at a butt joint (3) The connection of the sections which abut with their end surfaces is effected in that the abutting ends of the sections (1, 2) are surrounded jointly on the outside or on the inside by a steel pipe (4, 25), and also in that the surfaces of the sections (1, 2) or of the steel pipe (4, 25), which surfaces delimit the intermediate space (5, 26) between steel pipe (4, 25) and the sections (1, 2) and face one another, are roughened, and also in that the intermediate spaces (5, 26) are filled with mortar … …

Butt joint reactor

Abstract: PURPOSE:To shorten the average magnetic path length of a butt joint reactor by a method wherein an elliptic core leg is divided into two pieces at the center to form flat horseshoe-shape core legs, and the legs thereof are divided in the axial direction moreover. CONSTITUTION:Loop type laminated cores of two pieces of large and small are pressed from the outsides thereof to be deformed into the elliptic shapes, and then a heat treatment is applied to form elliptic yokes 2, 2' of two groups. Similarly, loop type laminated cores of two pieces of large and small are pressed to be deformed into the elliptic shapes, a heat treatment is applied, and the cores are divided into two parts vertically at the center thereof to form flat horseshoe-shape core legs 3, 3', 3'', 4, 4', 4''. Heat resistingly insulating plates having the prescribed magnetic resistances are inserted in space between the flat horseshoe-shape core legs. The core legs are arranged in series, and the necessary windings 5, 5' are wound around thereon.

Welding method of composite metallic material

Abstract: PURPOSE:To enable welding without fusing pasted metals to each other in the stage of welding composite metallic materials consisting of dissimilar metals, by projecting and working the pasted boundary parts of the dissimilar metals in the butt joint surfaces, sticking a flux thereon and subjecting the butt surfaces to electric resistance welding. CONSTITUTION:The part near the pasted boundary part K of butt end faces is projected H in the butt direction in the stage of the butt welding composite metallic materials clad with dissimilar metals 1, 2 to each other. The projecting parts H, H of both welding clad materials are butted to each other in such a way that the pasted boundary faces K of the metals 1, 2 coincide. The butt parts are heated by high, middler low frequency induction heating or electric resistance heating. A powder flux F such as a soda glass is supplied to the butt groove thereof, and while the flux is melted, both clad materials are pressed from both directions to extrude the molten flux from the butt parts and make the surfaces K of the dissimilar metals coincident, whereby moth metals are welded.

A Three-Dimensional Analysis of a Butt Joint with a Flaw

Abstract: A three-dimensional finite element method is employed to analyze an adhesive butt joint with a through-the-thickness crack in the center of the adhesive layer. The finite element model used accommodates both the extremely small dimensions of the adhesive layer and the larger dimensions of the rest of the region. The crack tip region is modelled by isoparametric quarter-point degenerate brick elements which give the required square root singularity for stresses at the crack tip. The results from a fracture mechanics approach corroborate the earlier experimental results that the strength of an adhesive joint increases with decrease in adhesive layer thickness. It is also observed that the stress intensity factor varies in a non-linear fashion along the crack front.

Buckling and loss of stability in reinforced cylindrical shell loaded by an internal gas flow of variable thermodynamic parameters

Abstract: 1. A cylindrical shell heated by an internal gas flow and subjected to the combined action of cold diaphragms and nonuniform heating over the perimeter of the section loses stability in the overheated zone by crumpling inward at lower temperatures than would occur separately for each of these loading factors. 2. Shells operating under conditions close to the operating conditions of tail pipes on gas-turbine engines must be built with a smooth stiffness transition from the flange to the shell and without longitudinal stiffeners, which might be longitudinal butt joints at abutting components, and overlap riveted, or welded butt joints in the shells.

Preparation of multi-layered orientation particle board

Abstract: PURPOSE:To reduce required energy, by a method wherein orientation particle boards with a specific thickness obtained by cutting a stock block along a surface parallel to the direction of a fiber axis are subjected to width-joint until a necessary dimension and the odd number of boards coated with an adhesive are laminated and clamped under pressure. CONSTITUTION:An adhesive used in wood is applied to a veneer 1 having a length of 1m or less in the fiber direction there of and laminated so as to be made parallel to the fiber direction as well as to arrange butt parts 2 in a dispersed state to be clamped and adhered under pressure to obtain a stock material block. After this stock material is cut along a surface vertical to the adhesive layer and parallel to the fiber diretion to form orientation particle boards each having a dimension of 1-10mm., these particle boards are subjected to butt joint until a necessary dimension to coat the adhesive used in wood. In the next step, the odd number of jointed boards are laminated so as to cross the fiber directions of adjacent layers obliquely or at right angles and clamped and adhered under pressure to obtain a multi layered orientation particle board.

Inert gas arc welding process employing a non-consumable electrode

Abstract: The inert gas arc welding process employing a non-consumable electrode consists of the following steps. Before the welding process the edges (5, 6) of a butt joint (1) are machined to produce a truncated surface (7) and the electrode is lowered the whole depth (h) of the weld seam. The truncated surface (7) is then melted over the whole thickness ( delta o) in the first pass and a weld root (8) of the first layer (9) is formed. With each successive pass the energy of the arc (4) per unit length is changed relative to the preceding pass. When a depth of h SIMILAR (0.3 to 0.4) delta of the weld seam is reached and its width is B SIMILAR (1.0 to 1.3)h, the electrode (2) is removed from the region of the weld seam and is arranged above the surface of the butt joint (1) in the region of the joint (3). Furthermore, the energy of the arc (4) per unit length is discontinuously raised compared to the preceding pass and the edges (5b, 6b) of the butt joint (1) are completely melted, with the formation of a layer (13) on the surface of the joint, whereupon the energy of the arc (4) per unit length is changed from pass to pass.