Abstract: A rock true triaxial dynamic compression-shear test equipment, and method under deep complex structure conditions, includes a counterforce framework, a pressure chamber, a base platform and four actuators. A pressure chamber transfer track is arranged on the base platform, and a pressure chamber transfer slipway is arranged on the tracks. The pressure chamber is a split structure. A pressure chamber base is located on the pressure chamber transfer slipway, and a pressure chamber barrel is provided with a pressure chamber barrel lift type bearing table and a pressure chamber barrel hoisting mechanism. The pressure chamber is provided with pressure chamber barrel and base packaging fixtures.

Abstract: A hybrid experimental-numerical approach is disclosed to determine the Mixed Mode (I/III) dynamic fracture initiation toughness of engineering materials. Cylindrical Aluminum alloy specimens with a V-notch spiral crack on the surface at spiral angles of 0°, 11.25°, 22.5°, 33.75°, and 45° are subjected to dynamic torsion load using torsional Hopkinson bar apparatus. The torque applied to the specimen at the onset of fracture is measured through strain gages attached to the incident and transmitter bars. A stereo digital image correlation is performed to measure the full-field deformation, and the crack mouth opening displacement as a function of loading time and is used to estimate the time at which the crack initiation is started. The dynamic stress intensity factors are extracted numerically based on the dynamic interaction integral method using Abaqus. The Mode-I (KId), Mode-III (KIIId), and Mixed Mode (K(I/III)d) dynamic initiation toughness is presented as a function of spiral angles and loading rate.

Abstract: A method for operating a pallet positioning station for positioning a pallet to be impacted by a pallet impact station is provided. The pallet positioning station includes a frame adjacent the pallet impact station, a pallet lift assembly carried by the frame that includes a lift grate moveable between a retracted position and an extended position, and a pallet push arm assembly carried by the frame that includes a pallet push arm movable between a retracted position and a pallet positioning position. The method includes moving the pallet push arm and the lift grate to the retracted positions to receive the pallet for positioning, moving the lift grate to the extended position when the pallet is to be positioned for impact by the pallet impact station, and moving the pallet push arm to the pallet positioning position to position the pallet towards the pallet impact station until the pallet is aligned with an impact reference plane.

Abstract: A pallet positioning station for positioning a pallet to be impacted by a pallet impact station includes a frame, and a pallet lift assembly carried by the frame. The pallet lift assembly includes a lift grate moveable between a retracted position and an extended position. A pallet push arm assembly is carried by the frame and includes a pallet push arm movable between a retracted position and a pallet positioning position. A controller is configured to move the pallet push arm and the lift grate to the retracted positions to receive the pallet for positioning, and move the lift grate to the extended position when the pallet is to be positioned for impact by the pallet impact station. The controller is further configured to move the pallet push arm to the pallet positioning position to move the pallet towards the pallet impact station until the pallet is aligned with an impact reference plane.

Abstract: Methods and systems to method to determine an adhesion force of an underfill material to a chip assembled in a flip-chip module are provided. A method includes forming a flip-chip module including a chip connected to a substrate with a layer of underfill material adhered to the chip and the substrate. The method also includes forming a block from the layer of underfill material. The method further includes measuring a force required to shear the block from a surface of the flip-chip module.

Abstract: Maximum allowable load values of a welded portion in respective fracture modes of a load fracture, a moment fracture, and a nugget interior fracture are found based on at least one of a sheet thickness t, a tensile strength TS, an elongation El, and a chemical composition of a nugget portion in each of spot-welded steel sheets, a nugget diameter d of a welded portion, an effective width B of the welded portion determined by a distance between adjacent welded portions, edges or ridge lines, and a sectional height H. Then, according to these fracture modes, an allowable load value at every moment after the maximum allowable load value of the welded portion is reached is found, and a displacement or a time at which the allowable load value becomes 0, that is, at which a complete fracture occurs is found, thereby finding a fracture limit.

Abstract: An apparatus (20) and method for characterizing stresses in a formation (10) based on leakoff pressure measured in the formation (10). The method includes determining a line of shear failure (52) as a function of leakoff pressure (LOP) measured in the formation (10), determining a vertical stress (Sv), and determining each of a lower limit (Sh,limit) and an upper limit (SH,limit) as a function of the vertical stress (Sv) and the leakoff pressure (LOP).

Abstract: The present invention related to a method, and an apparatus arrangement, for determining a fatigue limit for rolling contact initiated fatigue of a rolling bearing. The method comprises running a rolling bearing while being exerted to a load which generates sub-surface transformations in a rolling element contact zone of the outer or inner ring. Furthermore a set of sub-surface transformations in the contact zone along a raceway portion of the rolling bearing is identified and measured and used for generation of a parameter data set, wherein a fatigue parameter value representative of a predicted fatigue limit for the rolling bearing is determined based on the generated data set of sub-surface transformations.

Abstract: A binding force testing device for testing the binding force of a hinge, includes a control chassis for controlling the binding force testing device; a platform mounted on the control chassis; a support mounted on the control chassis above the platform; a first driving device mounted on the support; a main holder mounted on the first driving device facing the platform; and a second driving device mounted on the support and connected to the first driving device. The first driving device drives the main holder to move relative to the platform in a first direction; the second driving device drives the first driving device to move relative to the platform in a second direction perpendicular to the first direction.

Abstract: A method includes positioning a layer of adhesive between a first structural component and a second structural component, positioning a first evaluation film between the first structural component and the layer of adhesive, curing the adhesive at least partially, separating the first structural component and the first evaluation film by a relative movement therebetween, and inspecting bond line quality of the adhesive.

Abstract: A tack adhesion testing device for quantitatively measuring tack adhesion between a material and an object with a planar surface for contact with the material. The device has a material mount for mounting a quantity of the material such that the quantity of material presents an exposed flat face, an object mount for securely holding the object such that the planar surface is in flat contact with the exposed flat surface, the material mount and the object mount being movable relative to each other, a contact force applicator for applying a known force urging the exposed flat face and the planar surface into contact and, separation mechanism for applying a variable force to the material mount and the object mount to slide the flat face and the planar surface relative to each other such that the variable force can be increased until the flat face and the planar surface slide relative to each other.

Abstract: A tester for testing a shear fastener includes: a frame; a stationary chuck connected to the frame; a linear guide comprising a slider; a movable chuck connected to the slider; a movable insert fastened to the movable chuck and having a hole for receiving a first portion of the shear fastener; a stationary insert fastened to the stationary chuck and having a hole for receiving a second portion of the shear fastener; a linear actuator for engaging the movable chuck and fracturing the shear fastener; and a load cell for determining force exerted on the shear fastener by the linear actuator.

Abstract: A tester for testing a shear fastener includes: a frame; a stationary chuck connected to the frame; a linear guide comprising a slider; a movable chuck connected to the slider; a movable insert fastened to the movable chuck and having a hole for receiving a first portion of the shear fastener; a stationary insert fastened to the stationary chuck and having a hole for receiving a second portion of the shear fastener; a linear actuator for engaging the movable chuck and fracturing the shear fastener; and a load cell for determining force exerted on the shear fastener by the linear actuator.

Abstract: An apparatus (20) and method for characterizing stresses in a formation (10) based on leakoff pressure measured in the formation (10). The method includes determining a line of shear failure (52) as a function of leakoff pressure (LOP) measured in the formation (10), determining a vertical stress (Sv), and determining each of a lower limit (Sh,limit) and an upper limit (SH,limit) as a function of the vertical stress (Sv) and the leakoff pressure (LOP).

Abstract: An apparatus for adhering coupons together for adhesive shear testing may include a first member, a second member, at least one alignment device, and at least one separation device. The first member may have at least one first member cavity for holding at least one first member coupon. The second member may have at least one second member cavity for holding an overlapping area of at least one second member coupon adjacent to and separate from the at least one first member coupon. The overlapping area of the at least one second member coupon may be adhered to the at least one first member coupon. The at least one alignment device may control a size of the overlapping area. The at least one separation device may control a separation distance between the overlapping area of the at least one second member coupon and the at least one first member coupon.

Abstract: The invention relates to a cell for testing geomaterials on cylindrical specimens, of rock, ground or materials manufactured on sampling sites, including at least one piston for subjecting a specimen to a stress directed along the longitudinal axis of the specimen. According to the invention, the cell has, in addition, means for shearing the specimen, capable of cracking the specimen while it is being compressed in said at least one piston.

Abstract: A finite element method for predicting crack opening and propagation entails defining a succession of overlapping interface elements at a potential crack plane, each element having a bound node pair and side node pairs spaced from the bound node pair to sense approach of a crack. An energy-based fracture mechanics criterion determines whether release occurs at the bound nodes and, if so, the displacement between the bound nodes is calculated based on a strain softening law. The process is repeated for each element in sequence.

Abstract: A method provides early estimation of product life using accelerated stress testing data. In an embodiment, data measured from a product operating in a first, high-stress environment is used to predict how long the product will operate in a second, normal operating environment before failure using a quadratic acceleration model. An additional feature of the present invention provides a quantified indication of how much the product has improved from a redesign.

Abstract: An apparatus (10) for testing attachment features (26,28,30,32) of components (12,14) comprises a first member (16) having a first end (18), a second end (20), a first edge (22) and a second edge (24). The first edge (22) has a first firtree slot (26) to receive a first component (12) and the second edge (24) has a second firtree slot (28) to receive a second component (14). The first component (12) has a firtree attachment feature (30) to fit the first slot (26) and the second component (14) has a firtree attachment feature (32) to fit the second slot (28). The first end (18) of the first member (16) has flanges (34,36) extending laterally and the second end (20) of the first member (16) has flanges (38,40) extending laterally such that the first member (16) is substantially H-shaped in cross-section.

Abstract: A method of simulating life of a rotor blade mounting feature mounted in a complementary rotor disc mounting feature comprises the steps of providing two specimen mounting features (37) each having portions defining pressure faces matching in profile respective faces of the rotor blade mounting feature; providing a fixture (38) having two opposed mounting features (39) each having portions defining pressure faces (78) matching in profile respective faces of the rotor disc mounting feature; mounting the specimen mounting features (37) in the fixture mounting features (39); applying a first load to the specimen mounting features (37); measuring a strain in a region (86) of the fixture (38) between the fixture mounting features (39); applying a second load to the fixture (38), the second load being substantially perpendicular to the first load; and controlling the second load in response to the measured strain. A high cycle load may simultaneously be applied to the specimen mounting features (37).

Abstract: A system and method for non-destructively testing the strength of bonded joints, particularly a bonded joint between two composite components, is provided. The method generally includes activating a source of rapid surface pressure application against a bonded assembly containing the bonded joint to create a shock load. The resulting shock load first generates compression and then tension within the bonded joint, along with surface motions proximate the bonded assembly, and a surface motion detector measures the surface motions to determine the minimum strength of the bonded joint. Accordingly, the surface motions are correlated to the strength of the bonded joint. Further, the magnitude of the impact may be adjusted to vary the amount of tension within the bonded joint to correspond with various load conditions.

Abstract: Method for layered structure breaking strength estimation in which an edge of a cutting blade is inserted into an upper layer of the structure and the cutting blade is moved substantially in parallel with an interface between the upper layer and a lower layer of the structure while automatically controlling a depth of the cutting blade to a depth slightly higher than the interface. A force exerted on the cutting blade substantially in parallel with the interface is measured. An apparatus for performing the method is also disclosed.

Abstract: A method and art apparatus are proposed for inspecting solder balls on a BGA (Ball Grid Array) package, which are capable of rejecting defectively-bonded solder balls while allowing properly-bonded ones to pass therethrough. The proposed method and apparatus are characterized by the use of a rotatable disk having a plurality of flaps arranged at equal angular intervals along the perimeter thereof, and which is capable of being rotated in steps if a force greater than a preset threshold torque is being applied tangentially to any one of the flaps. The threshold torque is set to be equal to or less than the shear-resistant strength of a properly-bonded solder ball but greater than the shear-resistant strength of a defectively-bonded one. During an inspection procedure, the BGA package is moved toward the rotatable disk to allow each solder ball to push against one of the flaps on the rotatable disk.

Abstract: Focusing on the application of a predetermined relationship between the length of a fatigue damage detection sensor having a width of a specified shape and a required sensitivity or sensing accuracy (crack propagation rate), the present invention provides a fatigue damage detection sensor for structural materials and mounting method thereof, wherein when the length between a pair of fixing portions for fixing to a surface of a structural material M, both ends of a sensor body (2) sandwiching a notched portion (5) is defined as 2H, the length of a crack C that can propagate from a tip (5A) of the notched portion (5) is defined as (a), the number of times that a working load acts on the material is defined as N, and the crack propagation rate is defined as da/dN, the length 2H between said fixing portions is set so as to obtain a required sensitivity with which da/dN is proportional to H0.5m (m is a constant determined by a material).

Abstract: A back-to-back, single lap-joint test fixture and method provides for uniform shear strength determination in a lap-joint area at an adhesive bond plane between a low-modulus rubber-like elastic material substrate and a stiff panel both defining a single lap-joint specimen, two of which are disposed back-to-back with the rubber substrates being constrained from lateral deformation by respective aluminum housings each having a load-transferring lip pushing upon a substrate also being pulled by load transferring dowel pins pulling upon the rubber substrate while with a restraining clamp that restrains transverse movement of the housing and rubber substrate all so as to produce only shear-type failures based on the near-incompressible nature of the rubber materials in the two back-to-back single lap-joint specimens.

Abstract: A back-to-back, single lap-joint test fixture and method provides for uniform shear strength determination in a lap-joint area at an adhesive bond plane between a low-modulus rubber-like elastic material substrate and a stiff panel both defining a single lap-joint specimen, two of which are disposed back-to-back with the rubber substrates being constrained from lateral deformation by respective aluminum housings each having a load-transferring lip pushing upon a substrate also being pulled by load transferring dowel pins pulling upon the rubber substrate while with a restraining clamp that restrains transverse movement of the housing and rubber substrate all so as to produce only shear-type failures based on the near-incompressible nature of the rubber materials in the two back-to-back single lap-joint specimens.

Abstract: An apparatus and method for separating a thin film from a substrate, the thin film having a surface with a selected width, includes an indenter for applying a force to the surface of the thin film that is substantially equal along the selected width. The forces are applied until separation of a portion of the thin film from the substrate occurs. In a preferred embodiment, the indenter is made from a block of material having a substantially flat surface engageable with the surface of the thin film. The substantially flat surface of the block of material has a width at least equal to the width of the surface of the thin film. Based on the two dimensional geometry of the mechanics, accurate analysis of work of adhesion is achieved.

Abstract: A test apparatus for testing hem flanges that join automotive body panels is provided. This testing apparatus operates by engaging a hook member with a first body panel such that the first body panel is maintained in a held relationship with respect to the hook member. A ram member then extends from the testing apparatus and engages with and loads a second automotive body panel member. As a result, a tensile load is applied to the hem flange, permitting the hem flange to be analyzed for defective construction.

Abstract: A method and apparatus for testing the force required to remove flexible seals from objects such as product cups is disclosed. The object, e.g., cup is held so that the seal defines a substantially horizontal plane and a portion of the flexible seal is attached to a force measuring gripper. The object, e.g., cup is then moved away from the gripper at an angle .theta./2 with respect to horizontal. Forces are then measured by the gripper at an angle .theta. from horizontal. In a particular example, .theta. equals 45.degree. which simulates human removal of the flexible seal. The measured forces are digitized and stored for report generation.

Abstract: Apparatus is provided for obtaining a single crack in fatigue loading which emanates from a predetermined starting notch in a test specimen. This crack propagates in a direction in line with that of the applied Mode II load. The loading may be performed either monotonically or in a cyclic fatigue.

Abstract: A bi-axial compression test apparatus for geomaterial (soil, etc.) samples that is designed to allow free shear band formation and provide measurements of the stress displacement characteristics of the failure zone. A geomaterial sample formed into a specimen comprising a right rectangular prism is surrounded by a thin rubber membrane and is supported by walls along two parallel faces. An axial load is kinematically applied by a plate that is guided to prevent any tilt or eccentricity, while a bottom support plate for the specimen is horizontally guided by a linear bearing that is substantially friction free. All of the surfaces in contact with the specimen are glass lined and lubricated to minimize friction. The assembly of the specimen and its supports is placed in a conventional tri-axial cell in a loading frame so that an axial load can be applied to one end of the specimen and reacted against the bottom plate.

Abstract: In accordance with the present invention, a low in weight, portable, mechanical property testing machine is provided in which no special testing machine foundation is required, and a standard power supply may be used. The applied load to test the specimen is applied by the action of a rod making a single stroke within a cylinder containing hydraulic fluid. The inside diameter of the cylinder is significantly greater than the diameter of the rod. The hydraulic fluid transmitted from the cylinder is substantially ripple free and applies an even load to the specimen being tested through a second fluid cylinder and piston acting therein. The use of valves, as used in the prior art may thus be avoided, thus achieving simplicity of operation. To absorb the shock created by the specimen breaking, a dash pot is provided out board of the second piston as a shock absorber.

Abstract: A bi-axial compression test apparatus for geomaterial (soil, etc.) samples that is designed to allow free shear band formation and provide measurements of the stress displacement characteristics of the failure zone. A geomaterial sample formed into a specimen comprising a right rectangular prism is surrounded by a thin rubber membrane and is supported by walls along two parallel faces. An axial load is kinematically applied by a plate that is guided to prevent any tilt or eccentricity, while a bottom support plate for the specimen is horizontally guided by a linear bearing that is substantially friction free. All of the surfaces in contact with the specimen are glass lined and lubricated to minimize friction. The assembly of the specimen and its supports is placed in a conventional tri-axial cell in a loading frame so that an axial load can be applied to one end of the specimen and reacted against the bottom plate.

Abstract: An apparatus for testing the resistance to cleavage of cardboard tubes which have previously been cut into test pieces which includes a key mandrel which is mounted free to rotate, at least one sleeve for each test piece having a different outer diameter, the inner diameter of at least one sleeve being approximately equal to the outer diameter of a test piece so that for each test piece there corresponds at least one sleeve intended to house the test piece. The key mandrel is adapted to receive each test piece surrounded by a corresponding sleeve. A drive device and belt are provided to rotatably drive an assembly which includes the key mandrel and a test piece housed in a corresponding sleeve.

Abstract: An impact testing apparatus and process are provided. The apparatus comprises a thickness verifier to measure the thickness of each specimen. The apparatus further comprises a notcher and a notch verifier which are operative to first cut notches in a test group of specimens and to subsequently verify the accuracy of the notches. The apparatus further comprises a robotic gripper to sequentially deliver specimens to a vise for impact testing. The impact tester of the apparatus is operative to automatically assess the impact on each specimen. Additionally, the impact tester comprises optical sensors to assess the type of break of each specimen subjected to the impact test. A control unit receives input data from the various components of the apparatus, analyzes the data and prepares test reports.

Abstract: The bore hole rock shear testing device of the present invention comprises a case assembly having a longitudinal axis, a driving block, at least one wedge member, and a restraint member. The wedge member is positioned between the restraint member and the driving block and includes a rock engaging surface facing radially outwardly from the longitudinal axis of the case assembly. The driving block and the wedge member have complimentary tapered surfaces which cause the rock engaging surface to be urged radially outwardly when the wedge member is compressed or squeezed between the driving block and the restraint member. Power means are provided for moving the driving block toward the restraint member, and a restraint mechanism selectively holds the restraint member against movment.

Abstract: A device for determining the shear strength of rock and soil is disclosed. The device includes means for supporting the device within a borehole, a primary shaft, a plurality of shearing units slidably attached to the shaft having shear heads which are movable from a retracted position to a material-engaging expanded position, and a slip joint between adjacent shearing units such that the units operate independently from one another. The shearing units apply progressively greater normal forces on the material to be tested and sequentially shear the material being tested.In operation, the device is lowered into a borehole. Then the shearing units are moved from their retracted position to their expanded material-engaging position so as to apply progressively greater normal forces on the material to be tested. An axial force is then applied to the shaft so that the material engaged by the shearing unit closest to the anchor shears.

Abstract: An inexpensive device which is easily operated to accurately measure the Coulomb parameters of the soil. The Coulomb parameters are used in Coulomb's equation to calculate the shearing stresses along a failure surface of the soil. The device includes an instrument to test soil shear strength to which several weights have been added. To obtain the Coulomb parameters, the instrument is placed on the soil to be tested and weights are incrementally added to it. The instrument is rotated at each weight increment and the shearing stresses are read from its calibrated dial. The stresses are plotted on a graph from which the Coulomb parameters are determined. The shearing stress of the soil with any known force applied to it can then be determined.

Abstract: A compression shear test jig for determining the internal shear strength of the weakest plane of a wood fiber or particle panel product. The test jig comprises an upper and lower loading head adapted to be used in conjunction with a universal testing machine or press. The upper and lower loading heads are each provided with a sample engaging face disposed at substantially a 45.degree. angle. These faces are in parallel spaced apart relation. The bottom end of the lower face and top end of the upper face are each provided with a sample restraining element. The lower head body includes a base which rests upon a low friction surface permitting unrestrained lateral movement to occur as shear strain develops. Preferably the upper loading head includes a pivoted cap so that compressive force is applied uniformly. The sample engaging faces are preferably formed in separable face plates which are adjustable relative to the loading head bodies to compensate for samples of different thicknesses.

Abstract: Material properties related to strength are measured, using a force measuring device in cooperation with a testing device which is placed in contact with the material being measured while the material being measured is in a molten state, the testing device being such that the molten material can flow through at least a part of the testing device.

Abstract: Apparatus and a method are disclosed for measuring adhesion of particulate materials. A geometric object, such as a steel ball, is immersed in a sample of particulate material which is compacted to a predetermined density. The temperature of the sample is carefully controlled while the steel ball is pulled from the sample. The force required to pull the ball from the sample at a given temperature is recorded. Numerous tests conducted at different temperatures provide data to define a characteristic curve for a given particulate material. The apparatus and method is particularly useful for measuring the adhesion of aluminum powder such as that used as fuel in rocket motor solid propellant.

Abstract: A novel loading probe for fiber-matrix testing machines is made of diamond and has a truncated cone end for push-in and push-out tests of fibers in a fiber-matrix composite. The diameter of the probe body or shaft is greater than the diameter of the fiber to be pushed and the flat surface where the cone is truncated is at least one-half the diameter of the fiber. The included angle of the truncated cone is in the range of 55.degree. to 90.degree.. A useful compromise included angle is 70.degree..