532 results about "Strain energy" patented technology

A method for cutting a strengthened glass sheet through laser irradiation. The sheet includes a front surface layer and back surface layer each having a residual compressive stress and an intermediate layer which is formed therebetween and has an internal residual tensile stress CT (MPa). A strain energy U_CT (J/m²) expressed by U_CT={CT²×(t₁−2×DOL)}/(2×Y) is 2.5 J/m² or more. A cutting index K (N/mm) expressed by K=Pe/v×exp(−α×t₂)×(Y×α_L)/(t₂×ρ×c) is 150 N/mm or less.

A lightweight forward design method and system of automobile structure based on multi-performance constraints is disclosed. The finite element analysis model of automobile body structure is established by using finite element modeling technology. The typical force transfer path of automobile structure is identified by using topology optimization technology and the bending/torsional rigidity performance of automobile body is taken as constrained working condition, and lightweight design in conceptual stage is carried out. Then the strain energy analysis and the material thickness sensitivity analysis are carried out by using the sensitivity analysis technology, and the weak links and the critical design area of the vehicle body are found. Topography optimization is used to improve vehicle performance; Finally, based on business integration optimization software, The multi-performance target of automobile body is analyzed by integrated simulation, and the correlation between design parameters and performance, performance and performance is studied by using DOE sampling and data mining technology, and then the lightweight design of automobile body structure considering multi-disciplinary performance is carried out, which reduces the quality of automobile body structure, improves product performance, shortens R D and manufacturing cycle, and saves cost.

The invention provides a forecasting method for creep-fatigue life of a material. The method comprises the following steps: respectively performing a creep test, a fatigue test and a creep-fatigue interaction test for the material at a same test temperature; establishing a relation between the failure strain energy density wf and a non-elastic strain energy density dissipation rate of the material under a log-log coordinate according to the creep test; acquiring the fatigue damage df of the material per period according to the fatigue test; acquiring a hysteresis loop under a half-life period according to the creep-fatigue interaction test and establishing a function relation of the change of the stress Sigma (t) of the material under the half-life period within the maximum tensile strain maintaining time along with the change of time t; calculating the creep damage dc under the half-life period by combining with the hysteresis loop and based on the relation between wf and the function as shown in the specification and the relation of change of the fatigue damage df and the stress Sigma (t) along with the change of time t; and utilizing a linear accumulating damage rule to forecast the creep-fatigue life of the material under a creep-fatigue interaction. According to the method provided by the invention, the life of the material under the creep-fatigue interaction can be accurately forecasted.

A negative electrode for a lithium secondary cell having a collector composed of an electroconductive metal foil and, provided on the surface thereof, an active material layer containing active material particles containing silicon and/or a silicon alloy and a binder, characterized in that the binder has mechanical characteristics of a tensile strength of 50 N/mm² or more, an elongation at break of 10% or more, a strain energy density of 2.5×10⁻³ J/mm³ or more and a coefficient of elasticity of 10000 N/mm² or less, and preferably characterized in that the collector has mechanical characteristics of a tensile strength of 80 N/mm² or more, a proportional limit 30 N/mm² or more, an elongation at break of 1.0% or more and an elastic elongation limit of 0.03% or more.

The invention discloses a constant-resistance energy-absorbing anchor rod for strengthening a large-deformation rock body. The constant-resistance energy-absorbing anchor rod for strengthening the large-deformation rock body comprises a rod body, a constant-resistance energy-absorbing device, a nut and a tray, wherein the rod body is a smooth rod body with a round section; two ends of the rod body are provided with threads; the middle section of the rod body is wrapped by a plastic sleeve; the constant-resistance energy-absorbing device is arranged on the head part of the anchor rod and consists of a diameter-expanding cylinder, a conical cylinder, an anchorage device and a protective cover; the head of the rod body passes through the anchorage device to be connected with the diameter-expanding cylinder and the conical cylinder; and the protective cover is wrapped out of the diameter-expanding cylinder, the conical cylinder and the anchorage device. The constant-resistance energy-absorbing anchor rod can improve the capacity of the anchor rod in absorbing rock strain energy by utilizing the constant-resistance energy-absorbing device, is applicable to strengthening large-deformation surrounding rock of underground engineering or large-deformation rock creeping on the side slope under the high stress condition, has large ultimate elongation quantity, high and constant initial resistance and a simple structure, is convenient to manufacture and construct.

A carbon fiber reinforced substrate comprising a fabric composed of carbon fiber bundles and a first resin adhering to the fabric. Each of the carbon fiber bundles comprises numerous continuous carbon filaments, has the tensile modulus of 210 GPa or more, and has the fracture strain energy of 40 MJ/m³ or more. The amount of the first resin adhering to the fabric is in a range from 1 to 20 parts by weight per 100 parts by weight of said fabric. A preform comprising a laminate composed of plural layers of the carbon fiber reinforced substrate, wherein the layers are integrated by means of the first resin. A composite comprising the preform impregnated with a matrix resin.

A feedback control system for steering a tool along a well-plan. Optimum steering instructions may be generated by a recursive optimization of multiple objectives. These objectives can include accuracy and quality. The quality objective can include the objective of drilling a smooth borehole by minimizing strain energy and torsion. The accuracy objective can include the objective of minimizing the deviation of the borehole trajectory during the real-time drilling process from a predefined well-plan. The trajectory control problem, therefore, can be a multi-objective problem where, in some embodiments, the weightings of the individual objectives can be adjusted along the process.

The present invention provides spoke geometry for a non-pneumatic tire that is less prone to fatigue when used. In particular, the spoke geometry is provided with an optimized thickness profile over the length of the spoke. This optimization results in a reduction in the peak strain energy density levels in the spoke, thereby reducing the likelihood of crack initiation and propagation which in turn enhances the durability of the spoke and tire.

A framework for a deployable antenna is disclosed herein. The framework basically includes a plurality of elongate ribs, a matching plurality of foldable resilient members, and a hub. Each of the elongate ribs has both a proximal end and a distal end. The foldable resilient members serve to interconnect the proximal ends of the elongate ribs to the hub. Within such a configuration, each of the foldable resilient members is capable of storing strain energy whenever forcibly folded and also releasing the strain energy whenever subsequently permitted to elastically unfold. Thus, whenever the elongate ribs are released from a stowed position in which the foldable resilient members are forcibly folded, the strain energy causes automatic deployment of the antenna as the foldable resilient members are permitted to elastically unfold. In sum, therefore, the framework obviates many conventional uses of electro-mechanical motors or actuators in deploying various antennas.

A thin blanket epitaxial layer of SiGe is grown on a silicon substrate to have a biaxial compressive stress in the growth plane. A thin epitaxial layer of silicon is deposited on the SiGe layer, with the SiGe layer having a thickness less than its critical thicknesses. Shallow trenches are subsequently fabricated through the epitaxial layers, so that the strain energy is redistributed such that the compressive strain in the SiGe layer is partially relaxed elastically and a degree of tensile strain is induced to the neighboring layers of silicon. Because this process for inducing tensile strain in a silicon over-layer is elastic in nature, the desired strain may be achieved without formation of misfit dislocations.

The invention discloses a rope net unfolding device based on a thin-wall type stretching arm, which is used for ontrack cleaning of space debris. The device does not need to be driven by external power, and a net body structure is driven to unfold by strain energy stored by the thin-wall type stretching arm, so as to capture the space debris. Through adoption of a thin-wall structure, the stretching arm has high flexibility and light weight, the stretching arm stretches out and contracts back to store strain energy and to enable the mechanism to achieve a high magnification ratio. Due to the design that the stretching arm drives the net body structure to unfold, the unfolding process of the net body structure has good controllability; and due to the design of a press plate and a limiting pin, the unfolding synchronism is ensured.

A method of welding alloys having directionally-solidified grain structure. The methods improve the weldability of these alloys by creating a localized region of fine grain structure, wherein the welding occurs in these localized regions. The localized regions are formed by applying strain energy using a variety of different methods, such as by hammer peening, laser peening or sand blasting. Then, a heat treatment step may be used to create recrystallized grains having the fine grain structure. The region of fine grain structure provides better weldability.

A method and apparatus for controlling drilling, the method comprising ascertaining a current position and attitude of a drilling structure, obtaining a desired end point for the drilling structure, creating an optimized geometric Hermite curve path for the drilling structure from the current position and attitude of the drilling structure to the desired end point for the drilling structure and controlling a drilling of the drilling structure from the current position and attitude of the drilling structure to the desired end point for the drilling structure along the optimized geometric Hermite curve path.

The invention discloses a weld seam fatigue life calculation method based on total strain energy density. The method mainly comprises the steps that 1, the weld-seam total strain energy density, a life function equation and a fatigue strength coefficient, a fatigue strength index, a cyclic strengthening coefficient and a cyclic strain hardening index which are needed by half-cycle life stress and a strain function equation are acquired through a welded joint fatigue test; 2, the weld seam structure is simulated through a shell unit module, the stress-strain response of the weld seam structure under the cyclic load action is calculated through a multi-load step method, and a stress-strain hysteretic curve is output; 3, the total strain energy density is calculated according to the stress-strain response, and the hot point fatigue life and a damage value of a weld toe of the weld seam are calculated by combining the energy density with the life function equation. According to the method, contribution of elastic-plastic stress and strain to the fatigue damage is comprehensively taken into account, scalar quantities are taken as damage parameters, the position and direction problems related to vectors are effectively avoided, the calculation precision is improved, and the time is saved.

An epitaxially grown layer III-V solar cell is separated from the growth substrate by propagating a crack close to the epi/wafer interface. The crack is driven by the elastic strain energy built up due to thermal stresses between GaAs and polyimide by cooling below room temperature. A GaAs wafer is bonded to a polyimide substrate on the epi-side and scribed on the opposite side. The crack is initiated from the scratch and guided along the interface using an epitaxially grown sacrificial layer with lower fracture toughness under the solar cell. No expensive ion implantation or lateral chemical etching of a sacrificial layer is needed. The active layer is transferred wafer-scale to inexpensive, flexible, organic substrate. The process allows re-using of the wafer to grow new cells, resulting in savings in raw materials and grinding and etching costs amounting to up to 30% of the cost of the cell. Several cells are integrated on a common blanket polyimide sheet and interconnected by copper plating. The blanket is covered with a transparent spray-on polyimide that replaces the cover glass. The solar cell is stress-balanced to remain flat on orbit.

Wide bandgap materials, such as Gallium Nitride (GaN) and Silicon Carbide (SiC) are very promising for light-emitting diodes (LEDs) and power electronics. These materials are extremely hard and difficult to machine and very expensive. The lack of good quality bulk GaN substrates with a smooth surface at a reasonable price is hampering the development of vertical devices.

A rapid thinning technique is presented by lifting-off a 20-70 μm thick layer from the surface within a fraction of a second, which leaves the surface shiny and smooth. The savings in lapping and polishing add up to 60%, when this technique is incorporated in the crystal manufacturing process. This technology also has application for backside thinning where the savings are even larger.

The invention relates to a personalized interbody fusion cage design method based on topological optimization and bony reconstitution simulation. The method includes the steps of conducting CT/MRI scanning on a vertebral body, segmenting a CT/MRI continuous cross-sectional image of the vertebral body, establishing a three-dimensional model, establishing a finite element model through the substeps of grid dividing and smoothing, material assignment, boundary condition setting, mechanical loading and the like, conducting the topological optimization design on an interbody fusion cage through a density-variable method, and evaluating whether the design is reasonable or not by conducting bony reconstitution numerical analogue simulation on the vertebral body and the cage bone filling area according to the adaptation bony reconstitution theory on the basis of the strain energy density.

The invention relates to the field of rock fracture prediction, in particular to a shale hydraulic fracture propagation prediction method. The method comprises the steps that 1, the normal direction,tangential stress and effect stress of an inclined fracture under the action of the external stress and water pressure are calculated; 2, a strain energy density function is obtained according to thetype of the fracture; 3, a strain energy density factor is obtained according to the strain energy density function; 4, the propagation direction and propagation angle of the fracture are judged according to a strain energy density criterion; 5, influences of stratification, natural fractures and the like on the propagation direction of hydraulic fractures are obtained through numerical simulation, so that fracture propagation under the effect of shale hydraulic pressure is predicted. The prediction method is based on fracture mechanics, a hydraulic condition factor is introduced, and the influences of different stratification directions on the propagation direction of the shale hydraulic fractures are obtained by researching the relation between the fracture propagation direction and themagnitude of the hydraulic pressure and utilizing an extended finite element method, so that accurate prediction of hydraulic fracture propagation is achieved, and higher prediction accuracy is obtained.