Gm Global Technolgoy Operations, Inc.

James Dwight Cremonesi

Jianghuai Yang

Qigui Wang

Daniel J Wilson

Huaxin Li

Paul J Gelazin

Amit Kumar

Dale A Gerard

Mark R Claywell

Dale Edward Murrish

Balakrishna Chinta

Scott A Hucker

John B Fisher

A method for manufacturing a crankshaft for an internal combustion engine with a plurality of journals having a hardened case with a first microstructure. The crankshaft is comprised of a steel comprising between about 0.3 wt % and 0.77 wt % Carbon. The first microstructure of the hardened case of the journals comprises between about 15% and 30% ferrite and a balance of martensite and the resultant subsurface residual stress between 310 MPa and 620 MPa.

Crankshaft and method of manufacture

A damper for suppressing vibrations of a crankshaft of a vehicle is disclosed. The damper comprises a hub having a circular wall extending about a rotational axis to define a bore formed therethrough. The wall comprises a step portion radially extending therefrom and having a first arcuate portion formed thereon. The hub comprises a body portion radially extending from the wall to a lip to define an open cavity. The damper comprises a weld nugget disposed between the hub and the plate. The weld nugget has a root extending therethrough concurrent with the rotational axis to join the hub and the plate. The root has tip defining a profile such that the hollow channel is disposed at an angle tangent to the profile to lessen cracking due to stress.

Laser welded damper having enhanced fatigue performance

A nodular iron alloy and automotive components, such as a crankshaft, are provided. The nodular iron alloy may include iron, about 2.2-3.2 wt % carbon, about 1.7-2.3 wt % silicon, about 0.2-0.6 wt % manganese, a maximum of 0.03 wt % phosphorus, a maximum of 0.02 wt % sulfur, about 0.2-0.6 wt % copper, about 0.1-0.4 wt % chromium, about 0.4-0.8 wt % nickel, about 0.15-0.45 wt % molybdenum, about 0.2-1.0 wt % cobalt, about 0.02-0.06 wt % magnesium, and a maximum of 0.002 wt % rare earth element(s). The nodular iron alloy may have a Young's modulus in the range of 175-195 GPa and an as-cast ultimate tensile strength in the range of 750-950 MPa. This alloy possesses favorable strength, stiffness and noise/vibration/harshness qualities, making it suitable in crankshaft applications. A method of forming the nodular iron alloy includes feeding a magnesium-based material into a molten iron alloy through a continuous system at a constant amount.

High-modulus, high-strength nodular iron and crankshaft

A composite metal flexplate is disclosed that includes an aluminum center plate and a steel ring gear joined to the aluminum center plate by a solid-state joint. The solid-state joint that joins together the aluminum center plate and the steel ring gear may be formed by friction welding. During the friction welding process, a surface of an annular body of the steel ring gear is preheated, followed by bringing the preheated surface of the annular body into contact with a surface of a periphery of a circular body of the aluminum center plate. The two contacting surfaces are then caused to experience relative rotational contacting movement, which generates frictional heat therebetween and softens adjacent regions of the steel ring gear and the aluminum center plate. Once this occurs, an applied force is administered to compress and forge the contacting surfaces together, thereby establishing the solid-state joint.

Composite metal flexplate

A bearing shell for an automotive propulsion system is provided, along with a crankshaft assembly and an engine having a bearing shell. The bearing shell comprises an inner layer having an inner layer thickness. The inner layer defines a bearing surface on an inner side. The bearing surface of the inner layer is configured to support and contact an oil film. The bearing shell also has an outer layer disposed around the inner layer and radially outward of the inner layer. The outer layer has an outer layer thickness that is greater than the inner layer thickness, the outer layer thickness being at least one millimeter. The outer layer is formed of an outer layer material comprising an aluminum alloy and/or a metal matrix composite material. The inner layer is formed of an inner layer material, wherein the outer layer material is stronger than the inner layer material.

Bearing with lightweight backing substrate

A sand casting apparatus, a method of forming a sand casting apparatus, and an automotive component are provided. The sand casting apparatus includes a sand casting base including a sand mold and/or a sand core having a base sand mixture, where the base sand mixture includes a sand material and a binder material. The sand casting apparatus further includes an outer layer disposed on the sand casting base. The outer layer includes silicon, magnesium, calcium, zirconium, manganese, carbon, aluminum, and iron. The automotive component has portions defining an aperture therein. The automotive component is formed of cast iron and has a nodular graphite structure from interior matrix to surface, where the nodular graphite structure on the surface is formed by a sand core having an outer layer that has reacted with the cast iron automotive component to form the nodular graphite structured surface.

Sand core to eliminate degenerated skin

A method of manufacturing a crankshaft assembly includes configuring a crankshaft with a crankpin journal having a cavity extending at least partially from a first axial side to a second axial side of the crankpin journal, and opening at at least one of the first axial side and the second axial side. The method includes disposing a core plug in the cavity. The crankshaft has a first density and the core plug may have a second density which may be less than the first density. A crankshaft assembly includes the crankshaft and the core plug.

Growing community of inventors

Rochester Hills, MI, United States of America

James Dwight Cremonesi