Gm Global Technolgoy Operations, Inc.

Cherng-Chi Chang

Qigui Wang

Bing Li

Bob Ross Powell

Wenying Yang

Devin R Hess

Peggy E Jones

Yi Liu

Richard L Metcalf

Angela Zsidi Alksninis

Michael J McCreedy

Jayaraman Sivakumar

Michael R Harper

Bhuvaneswara R Dharmavarapu

David Paluch

Guihua Zhang

Purushotham Kunduru

An engine block for a vehicle includes a bore surface defining a cylinder bore. The bore surface exhibits a first microstructure and includes a pattern of a plurality of cycloidal features formed in the bore surface. The plurality of cycloidal features each exhibit a first length in a first axis and a second length in a second axis arranged 90 degrees from the first axis. The plurality of cycloidal features also exhibit a ratio of the first length to the second length in a range of 1:1.5 to 1.5:1. The plurality of cycloidal features further exhibit a second microstructure including tempered martensite, wherein the second microstructure is different from the first microstructure. The engine block is included in a vehicle. The cycloidal features are formed with a laser.

Laser hardened pattern array in cylinder bores

A method, device and article of manufacture for determining properties in a high pressure die cast component. Upon receipt of geometric information that corresponds to a location of interest within the component, a ray-triangle intersection relationship is used to calculate a wall thickness of the location of interest; this relationship is simplified by being used in conjunction with an octree-based relationship. One or more calculations are performed to determine a skin thickness based on the calculated wall thickness, and the skin thickness calculations are based on at least one of a logarithmic relationship, a polynomial relationship and a power law relationship. Changes in component shape or size may be taken into consideration to adjust the remaining skin layer thickness, such as that when the as-cast component is exposed to subsequent machining or related post-casting operations. From this, the properties are mapped to allow node-by-node variations in mechanical properties based on whether the node resides in the component skin region or core region.

Method to incorporated skin and core material properties in performance analysis of high pressure die casting aluminum components

A cylinder liner for an engine block includes a first engine block bonding surface, and a second engine block bonding surface that provides a lower heat transfer coefficient between the cylinder liner and an adjacent engine block material than the first engine block bonding surface. The second engine block bonding surface extends a substantial portion of the axial length of the cylinder liner.

Cylinder liner for internal combustion engine

The invention relates to a method for estimating heat transfer during water quench of an aluminum part. The method includes: 

Method for simulating transient heat transfer and temperature distribution of aluminum castings during water quenching

Computational systems, methods, and articles of manufacture to predict at least one of residual stresses and distortion in quenched aluminum castings. Residual stresses and distortion may be predicted through incorporating thermal strains induced during quenching with the nonlinear constitutive behavior of quenched microstructures of a quenched aluminum casting, wherein thermal strains arise generally from non-uniform transient temperature distribution of the casting during quenching. The transient temperature distribution of the aluminum casting during quenching may be calculated based on heat transfer coefficients specific to one or more nodes, elements and/or zones on the surfaces of the aluminum casting. The nonlinear constitutive behavior of the quenched aluminum casting may be modeled as functions of temperatures, strain rates, and microstructure variations. A material constitutive model accounts for not only strain hardening and creep, but also precipitate hardening. Thereby, residual stresses and distortion in the quenched aluminum castings can be predicted using the embodiments.

Methods of predicting residual stresses and distortion in quenched aluminum castings

A system and method for predicting fatigue life in metal alloys for very high cycle fatigue applications. The system and method are especially useful for cast metal alloys, such as cast aluminum alloys, where a fatigue endurance limit is either non-existent or hard to discern. Fatigue properties, such as fatigue strength in the very high cycle fatigue region, are based on a modified random fatigue limit model, where the very high cycle fatigue strength and infinite life fatigue strength are refined to take into consideration the sizes of the discontinuities and microstructure constituents since the fatigue life scatter depends upon the presence of discontinuities and microstructure constituents. The sizes of the discontinuities and microstructure constituents that can initiate fatigue cracks can be determined with extreme value statistics, then input to the modified random fatigue limit model.

Methods and systems for predicting very high cycle fatigue properties in metal alloys

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Troy, MI, United States of America

Cherng-Chi Chang