Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A method of joining first and second parts formed of dissimilar materials is provided. The first part defines a first part contacting surface having a frustoconical shape. The first and second parts are brought into contact with one another, with one of the first and second parts being rotated while the other remains stationary, so as to generate frictional heat between the contacting surfaces of the parts, the generated frictional heat producing softened adjacent regions in the first and second parts. A force is applied to the first and second parts to plastically deform the softened adjacent regions and to forge together the first and second parts to form a solid-state joint. A composite torsional damper hub assembly includes a steel stem and a damper hub welded to the stem at an interface. The damper hub is formed of aluminum or an aluminum alloy, and the interface is generally frustoconical.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A nodular iron alloy and automotive components, such as crankshafts, are provided. The nodular iron alloy may include iron, about 3.3-3.9 wt % carbon, about 0.2-0.5 wt % manganese, about 1.9-2.6 wt % silicon, about 0.15-0.30 wt % copper, about 0.03-0.06 wt % magnesium, about 0-0.02 wt % sulfur, about 0-0.1 wt % chromium, about 0-0.05 wt % phosphorus, and/or about 0-0.01 wt % tin. The nodular iron alloy may include a number of graphite nodules, each having a diameter between 15 and 120 micrometers, and the graphite nodules having a number density of at least 90 per square millimeter. Iron may surround the graphite nodules in an amount of 20-40% of a ferrite microstructure and 60-80% of a pearlite microstructure. The nodular iron alloy may have an ultimate tensile strength in the range of 550 MPa to 680 MPa as-cast and at least 80% nodularity.

Abstract: A steel alloy and automotive components, such as crankshafts, produced therefrom are provided. The steel alloy includes iron, about 0.34 to about 0.40 weight percent carbon, about 0.8 to about 1.2 weight percent manganese, about 0.40 to about 0.60 weight percent silicon, about 0.04 to about 0.07 weight percent sulfur, about 0.9 to about 1.2 weight percent chromium, about 0.20 to about 0.35 weight percent molybdenum, about 0.08 to about 0.15 weight percent vanadium, and about 0.02 to about 0.06 weight percent aluminum. The steel alloy may also include up to 0.03 weight percent phosphorus, up to 0.25 weight percent nickel, up to 0.20 weight percent copper, up to 0.03 weight percent titanium, up to 0.03 weight percent nitrogen, and up to 0.002 weight percent boron.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A method for heat treating a crankshaft surface on a crankshaft for a vehicle propulsion system includes heating the crankshaft surface to a first temperature and heating the crankshaft surface to a second temperature that is higher than the first temperature.

Abstract: 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.

Abstract: A high-strength steel alloy and automotive components produced therefrom, as well as a method for forming a steel alloy, are provided. The high-strength steel alloy includes iron, about 0.24 to about 0.80 weight percent carbon, about 0.40 to about 2.10 weight percent manganese, about 0.20 to about 1.60 weight percent silicon, about 0.05 to about 0.14 weight percent sulfur; about 0.10 to about 12.0 weight percent chromium, about 0.10 to about 2.50 weight percent nickel, and about 0.02 to about 0.07 weight percent aluminum. The steel alloy may also include boron, molybdenum, titanium, niobium, and/or nitrogen. The method includes air quenching a steel alloy component after mold shakeout until the component reaches a temperature in the range of 420 to 530 degrees Celsius.

Abstract: 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.

Abstract: 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 comprising a sand mold and/or a sand core comprising a base sand mixture, where the base sand mixture includes a sand material and a binder material. The sand casting apparatus further comprises an outer layer disposed on the sand casting base. The outer layer comprises 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.