98results about How to "Reduced fatigue life" patented technology

A high strength Al-Mg alloy in plate or extrusion form having significantly improved strength in both soft and work-hardened tempers as compared with AA5083 is provided. The materials have ductility, pitting, stress and exfoliation corrosion resistances equivalent to those of the AA5083. The materials have improved long term stress and exfoliation corrosion resistances at temperatures above 80° C. The composition is 5-6% Mg, >0.6-1.2% Mn, 0.4-1.5% Zn, 0.05-0.25% Zr, up to 0.3% Cr, up to 0.2% Ti, up to 0.5% each Fe and Si, up to 0.4% each Cu and Ag, remainder Al and inevitable impurities. Manufacture of plate of this alloy is by homogenizing an ingot, hot rolling the ingot into plate in the range 400-530° C., cold rolling the plate with or without inter-annealing, final and optionally inter-annealing of the cold rolled material at temperatures in the range 200-550° C.

A method for producing an over-running decoupler that is configured to transmit rotary power between a rotary member and a hub. The over-running decoupler includes a one-way clutch having a clutch spring, a carrier that is coupled to the clutch spring and at least one spring that resiliently couples the carrier to the hub. The method includes: establishing a desired fatigue life of the at least one spring; establishing a design deflection of the at least one spring during resonance, wherein deflection of the at least one spring at the design deflection during resonance does not reduce a fatigue life of the at least one spring below the desired fatigue life; and preventing resonance in the over-running decoupler by controlling a maximum deflection of the at least one spring such that the maximum deflection is less than or equal to the design deflection.

An electronic module and method of fabrication are provided employing an integrated thermal dissipation assembly. The thermal dissipation assembly includes a thermoelectric assembly configured to couple to an electronic device within the module for removing heat generated thereby, and a programmable power control circuit integrated with the thermoelectric assembly. The programmable power control circuit allows cooling capacity of the thermoelectric assembly to be tailored to anticipated heat dissipation of the electronic device by adjusting, for a given power source, voltage level to the thermoelectric elements of the thermoelectric assembly. Power to the thermoelectric assembly can be provided through conductive power planes disposed within a supporting substrate. The power control circuit includes one or more voltage boost circuits connected in series between the given power source and the thermoelectric elements of the associated thermoelectric assembly.

The invention provides a method for manufacturing a large-curvature aluminum alloy integral wall board component. The method includes the steps that A, solution hardening is conducted on a wall board; B, the wall board obtained in the step A is arranged in a sealed environment formed by a thin film covering layer and a forming die jointly, the wall board is elastically deformed and plastically deformed in sequence under the vacuumized condition, and then the deformed wall board is obtained, wherein the temperature in the sealed environment where the wall board is located ranges from 15 DEG C to 35 DEG C, the vacuum degree ranges from -0.1 MPa to -0.05 MPa, and the treatment time ranges from 5 min to 60 min; C, in-situ creep stress relaxation aging is conducted on the deformed wall board obtained in the step B, wherein creep stress relaxation aging time is more than 2 h; D, unloading operation is conducted, and then the large-curvature aluminum alloy integral wall board component is obtained. When the method is used for manufacturing the large-curvature aluminum alloy integral wall board component, the residual stress of the product is greatly reduced, the strength of the product is improved, and the product with high forming accuracy and good performance is obtained.

The present invention provides a drum or rotor wheel hub having a cast hub having a machined pilot in a flange portion and a machined pilot in a cylindrical portion, and a cast portion which separates the cylindrical pilot from the flange pilot, whereby a machined radii is not incorporated in the pilot construction.

A steam turbine blade in which the turbine blade has a blade root of the axially-inserted fir tree type and a larger number of turbine blades can be attached in a restricted outer peripheral region of a turbine rotor by arranging the blade root to be oriented in a direction forming a predetermined angle α larger than 0° relative to the axial direction of the turbine rotor. The steam turbing blade can suppress peak stresses generated at the bottoms of notches formed in the blade root and a blade groove and also suppress fretting fatigue from being induced by contact between peak stress generating areas and areas opposed to the peak stress generating areas at the notch bottoms. The steam turbine blade includes an airfoil, and a blade root attached to a turbine rotor and having plural stages of hooks in the radial direction of the turbine rotor.

A method for repairing minor defects in a workpiece using flame spraying is provided. The method includes first providing a workpiece having a defect and an area proximate to the defect. The method also includes routing a portion of the workpiece, including the defect, such that the routing removes at least a portion of the workpiece proximate to the defect. The depth to which the workpiece is routed may be controlled with a micro-stop countersink apparatus. A router bit is generally plunged into the workpiece in a direction orthogonal to the surface of the workpiece such that the routed portion of the workpiece defines a sidewall extending generally orthogonal to the workpiece and a conical bottom surface. The portion of the workpiece that has been removed by routing is then flame sprayed such that new material is added to fill the portion of the workpiece that has been routed.

The invention provides a dog-bone joint beam end buckling constraining device. The device comprises constraining cover plates (1), constraining U-steel (2), filling plates (3) arranged between the constraining cover plates and the constraining U-steel, and connecting bolts (4), wherein the constraining cover plates (1) are arranged on the outer sides of upper and lower flange weakening parts (7-1) at the ends of a steel beam (7) provided with a dog-bone joint; the constraining U-steel (2) is arranged on the portions, corresponding to the two sides of a web, of the flange weakening parts; and the connecting bolts (4) are used for connecting the constraining cover plates, the constraining U-steel and the filling plates to form the complete constraining device. When an earthquake occurs, the beam end flange weakening parts yield in advance of other parts and components, earthquake energy is dissipated through the hysteretic characteristic, and by adoption of the constraining device, press on the beam end flange weakening parts and large-amplitude buckling possibly occurring outside the plane of a steel plate when the corresponding web is pressed and sheared can be limited, shortening of the fatigue lives of the flange weakening parts and degradation of joint rigidity and strength are prevented, the steel beam (7) in a joint area is protected against complete buckling outside the plane, the fullness of a hysteretic curve is ensured, and the joint deformation capacity and ductility and the lateral stability of the beam are improved.

An anodic oxide film is formed on an aluminium or aluminium alloy work piece by forming an anodic oxide film on the work piece by AC electrolysis followed by subjecting the work piece to DC electrolysis. The AC anodising step may be conducted at a voltage of 5 to 30V for 30 seconds to 10 minutes and the DC anodising step may be conducted at a voltage of 5 to 30V for a period of 1 to 20 minutes. The anodic oxide coating is suitable for adhesive bonding of aluminium alloy work pieces.

The invention discloses a preparation method of a cup-shaped flexible wheel and a device thereof. A circular slab is tightened at the end of a core die by a tail top. A positive wire of a pulse powersupply is connected with the core die, and a negative wire is directly connected with each rotary wheel of a rotary wheel assembly. The circular slab is first spun and deformed into a cup-shaped workpiece with both inner and outer walls being straight walls by one rotary wheel. Then the cup-shaped workpiece is spun and deformed into two thickened cup-shaped workpieces with different straight wallthickness by another two rotary wheels, and a thicker smooth section is used as a tooth profile reserved section. Finally, the tooth profile reserved section is spun by one toothed rotary wheel to form a circle tooth profile around the outer circumference. At last, a small amount of cutting process is carried out to complete the processing process from the circular slab to the cup-shaped flexiblewheel workpiece. According to the cup - shaped flexible wheel manufacturing process based on plastic forming, streamline formed in the process of deformation can be completely retained, and the service life of parts is prolonged advantageously. The advantage of the method is more obvious for flexible wheels with an extremely small thickness.

A pin bearing arrangement for use on an aircraft landing gear includes a pin and a load sensor arrangement, which may include strain gauges for measuring shear loads and accelerometers for measuring loads sustained by the pin. The pin includes a self-contained data logging device for logging data concerning loads sustained by the pin. Thus, inside the pin, there may be provided a processing unit, a memory store, and a battery-based power source. During normal operation of the aircraft fatigue loads may be monitored, the processing unit receiving input signals from the means for measuring loads and storing load data in the memory. The stored load data may periodically be extracted from the memory during maintenance of the aircraft.

Provided are a bearing device for a wheel, in which circumferential play is reduced, which provides excellent workability in connection between a hub ring and an outer joint member of a constant velocity universal joint, in which fitting between the hub ring and the outer joint member of the constant velocity universal joint is stable, and which has excellent strength, and an axle module using the bearing device. An axially extending projection is formed on either of the outer diameter surface of a shaft section of the outer joint member and the inner diameter surface of a hole of the hub ring. The projection is press-fitted to the other in the axial direction to form a recess in the other by the press-fitting. By this, a recess/projection fit structure is formed, in which the entire regions of those portions of the projection and the recess at which they are fitted to each other are in intimate contact with each other. The hardness of at least that portion of the projection at which the press-fit starts is higher than that of a portion where the recess is formed. The difference in hardness in HRC is 20 or more.

The invention relates to a super advanced double-phase stainless steel smelting process method of a CD3MWN material. According to the invention, internal control components during double-phase stainless steel smelting is designed, wherein C is less than or equal to 0.030 wt%, Si is less than or equal to 0.90 wt%, Mn is 1.20-2.50 wt%, P is less than or equal to 0.020 wt%, S is less than or equal to0.015 wt%, and Cr is 26.2-27.5 wt%, Ni is 6.2-7.6 wt%, Mo is 2.2-3.4 wt%, Cu is less than or equal to 0.80 wt%, W is less than or equal to 0.80 wt%, N is 0.32-0.38 wt%, B is 0.0010-0.0100 wt%, Ba is0.0002-0.0100 wt%, and Ce+La is 0.005- 0.030 wt%; and %Cr+3.3 (%Mo+0.5%W)+16%N is less than or equal to 45, the content of trace elements B, Ba, Ce, and La can be precisely controlled; the N content is increased to 0.30% or more, and at the same time, nitrogen holes in the casting can be avoided; and the content of harmful elements such as sulfur, oxygen, hydrogen and the like is minimized to improve the purity of the molten steel. The cast casting has high strength and excellent corrosion resistance. In the stainless steel, a ferrite phase and an austenite phase are close to 50%, the castinglife is prolonged. the production costs are greatly reduced, and purposes of energy saving and environmental protection can be realized.

The invention aims to provide a wheel rim fatigue analysis method which comprises the steps that A, boundary constraint conditions, material parameters and working conditions are preset, and a tested wheel rims model is established with a finite element method; B, loads in six directions are applied to the model, stress nephograms are established, stress concentration points under the loads in all directions are determined as dangerous points, and dangerous load directions are determined in the six directions; C, Mises stress ad stress in X, Y and Z directions of the dangerous points determined by all the nephograms and tested known dangerous points are measured, and the largest direction stress is determined as the stress direction of the dangerous point; D, fatigue lives N in all test areas are calculated by combining the preset material parameters and the strass data obtained in the step C, and the calculated minimum value in the fatigue lives is the minimum fatigue life of the tested wheel rim. The wheel rim fatigue analysis method overcomes the defects that the design and development cycle of a wheel rim is long and the cost is high in the prior art and has the advantages of accurate calculation and high calculation efficiency.

A method for preforming of two or more flexible cables in an arrangement consisting of a combination of rigid printed circuit boards and flexible cable sections extending therebetween. Moreover, also provided is an apparatus for the preforming of two or more flexible cable sections of a combination of rigid printed circuit boards and therewith interposed flexible cable sections which are adapted to interconnect the rigid printed circuit boards. The apparatus consists of a tool constituted of an elongated cylindrical member having a tapered leading end which narrows into an ultra-thin flat end section of a blade-like configuration, and which is adapted to be pushed between the flexible cables and so as to preform the flexible cable sections and cause them to yield in a predetermined outwardly bowed permanently relationship between the rigid printed circuit boards at the opposite ends thereof to lengthen the fatigue life of the conductors in the flexible cable sections.

The invention provides a preparation method of a high-reliability long-service-life silicon nitride ceramic ball for an aircraft bearing, and belongs to the technical field of silicon nitride ceramicball manufacturing. Metal organic salt (aluminum isopropoxide and metal acetate) is used as a precursor of a sintering aid, and the surface of silicon nitride can be coated with the sintering aid through hydrolysis, spray drying and calcination processes, so that uniform dispersion of the sintering aid in silicon nitride is realized; therefore, the reduction of reliability and fatigue life of theceramic ball caused by agglomeration and segregation of the sintering aid is avoided. The result of the embodiment shows that the density of the silicon nitride ceramic ball prepared by the method reaches 99.9% or above, the Vickers hardness (HV10) is larger than 1500, the crushing load ratio is larger than 45%, the Weibull modulus is larger than 15, the rolling contact fatigue life (RCF) is 400 hor above, and the silicon nitride ceramic ball is particularly suitable for manufacturing rolling elements for aviation bearings.

A fixed constant velocity universal joint using eight torque transmitting balls hasa ratio which a non-hardened layer assumes in a bar 48 of a cage 40 is set to be 0.30≦C/S≦0.75, where S represents a cross-sectional area of the bar 48 and C represents an area of the non-hardened layer.

A high strength casting aluminum alloy material comprises (in weight %) Cu 2.0-6.0%, Mn 0.05-1.0%, Ti 0.01-0.5%, Cr 0.01-0.2%, Cd 0.01-0.4%, Zr 0.01-0.25%, B 0.005-0.04%, rare earth 0.05-0.3%, and balance aluminum and trace impurities. The alloy has reduced cost.

The invention relates to a dual-channel heat transmission heat exchanger with a rectangular heating pipe and a manufacturing process of the dual-channel heat transmission heat exchanger. The heat exchanger comprises outer heat supply pipes the longitudinal sections of which are rectangular, wherein the outer end of each outer heat supply pipe is plugged through an end socket closure plate; a notch is correspondingly arranged on the pipe walls of the same ends of the two adjacent heat supply outer pipes, another notch is arranged on the other same ends of the next adjacent outer heat supply pipes are correspondingly, and the outer heat supply pipes are communicated through the notches; the outer heat supply pipes are internally provided with tap water heat absorption pipes which are communicated through tap water communicating pipes, and the tap water communicating pipes pass through the notches; and inner heat supply pipes are arranged in the tap water heat absorption pipes, and the inner heat supply pipes are communicated with a cavity body of the outer heat supply pipes. According to the heat exchanger and the manufacturing process, the effective heat energy is utilized fully, a double-pipe cold fluid wall of at the center of a pipe cavity is heated, the heat-transfer area is increased, heat fluid and cold fluid are heated in a circulating manner by three channels, and the heat transfer efficiency is improved. A stainless steel thin wall pipe, a plate manufacture punching, stretching and flanging are adopted; the thin wall stainless steel welding difficulty is reduced due to the embedding type, the side pinched, so that the welding is easy, and acid is filled in an inner channel for cleaning scale generated in the inner channel.

The invention discloses a friction welding type full titanium alloy drilling rod and belongs to the technical field of drilling rods. The drilling rod comprises a rod body made of titanium alloy and further comprises a joint made of titanium alloy, and the rod body is connected with the joint in a friction welding mode. The friction welding type full titanium alloy drilling rod aims at reducing the whole weight, preventing the connection segment between the drilling rod joint and the drilling rod body from generating displacement and bending stress, improving the connection stability, reducing the stress concentration and prolonging the fatigue life of the drilling rod.

The invention relates to a processing technology for a spring made of a titanium alloy wire with a special-shaped section and belongs to the field of metal material processing. Titanium alloy components include the following elements in percentage by mass: 2-4 of Al, 8-11 of V, 4-8 of Cr, 4-8 of Mo, 3.5-6 of Zr and the balance of Ti. The spring is wound by using the titanium alloy wire with the special-shaped section, the titanium alloy wire with the special-shaped section, which is used for winding the spring, is prepared by using processes of ingot forging and cogging, finish forging, hot drawing and cold rotary forging, and the section of the wire can be shaped like a square, a rectangle, a regular hexagon and a regular octagon. Compared with a steel spring, the titanium alloy spring has favorable corrosion resistance and fatigue resistance and is stable in performance and obviously prolonged in life when being used in environments such as sea and other corrosive environments. In addition, the titanium alloy is relatively low in density which accounts for about 60% of that of steel, and therefore, a weight reducing effect can also be achieved if the steel spring is replaced with the titanium alloy spring.