A repair method for repairing a crack generated to a cast steel member due to a thermal stress includes removing a part of the cast steel member including the crack at a surface of the cast steel member to form a recess, fitting into the recess a first repair member that is made of a metal that is more flexible than the cast steel member and that is weldable to the cast steel member, and spot welding the first repair member to the cast steel member.

A hard faced surface comprises a metal substrate. Inserts are attached to the substrate as a covering layer on the substrate. Each insert comprises a thermally stable polycrystalline diamond (TSP) body (or polycrystalline diamond or cubic boron nitride) having a plan section, a contact surface and a flat top surface. A boundary coating on the ultra-hard body renders the body wettable by first braze material. A tungsten carbide cap is brazed with said first braze material to at least the top surface of the TSP block. The inserts are brazed to the substrate in a closely packed side-by-side formation with a second braze material that penetrates the gaps between the inserts and between the contact surface of the bodies and the metal substrate. The tungsten carbide caps of the inserts provide a gauge for the hard faced surface, which caps are ground in a finishing step exposing the caps and providing the hard faced surface with a desired dimension including an amount of the thickness of the caps.

A method for manufacturing a ring gear/differential case assembly includes attaching a ring gear to a differential case. The ring gear and the differential case are fabricated of materials having differing properties. The attaching includes placing a first portion of the ring gear in intimate contact with a first portion of the differential case whereby a predetermined gap is defined between another portion of the ring gear and another portion of the differential case. The ring gear first portion is attached to the differential case first portion by a friction welding process. The predetermined gap defines an outflow channel for receiving an overflow material created by an upset forging step of the friction welding process. Differential assemblies and vehicles including such are described.

Pistons and methods of making the same are disclosed. An exemplary piston assembly may include a piston crown and skirt. The crown may include a crown collar wall extending downward toward a free end of the crown collar wall. The skirt may include a pair of oppositely disposed pin bosses that each define piston pin bores configured to receive a piston pin for securing a connecting rod between the pin bosses. The skirt may further include a radially inner skirt mating surface abutted along a radially inner interface region with the radially inner crown mating surface, and a radially outer skirt mating surface abutted along a radially outer interface region with the radially outer crown mating surface such that a cooling gallery is substantially enclosed. The skirt may further include an inner collar wall extending upwards to the free end of the crown collar wall.

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.

Methods and systems for generating a laser beam with different beam profile characteristics are provided. In one aspect, a method includes coupling an input laser beam into one fiber end of a multi-clad fiber, in particular a double-clad fiber and emitting an output laser beam from the other fiber end of the multi-clad fiber. To generate different beam profile characteristics of the output laser beam, the input laser beam is electively coupled either at least into the inner fiber core of the multi-clad fiber or at least into at least one outer ring core of the multi-clad fiber, or a first sub-beam of the input laser beam is coupled into at least into the inner fiber core of the multi-clad fiber and a second, different sub-beam of the input laser beam is coupled at least into the at least one outer ring core of the multi-clad fiber.

The invention concerns a method for generating a laser beam (3) with different beam profile characteristics, whereby a laser beam (2) is coupled into one fiber end (1a) of a multi-clad fiber (1), in particular a double-clad fiber, and emitted from the other fiber end (1b) of the multi-clad fiber (1) and whereby, to generate different beam profile characteristics of the output laser beam (3), the input laser beam (2) is electively coupled either at least into the inner fiber core (4) of the multi-clad fiber (1) or at least into at least one outer ring core (6) of the multi-clad fiber (1), as well as a corresponding arrangement (10).

Casting a metallic object by constructing a plurality of production layers with mold regions and object regions within the mold regions, includes a mold construction unit, a Preparation-Deposition-Post treatment (PDP) unit, a build table; and a movable unit to move the PDP unit with respect to the build table. The PDP unit includes: a holder; induction heater(s) having hole(s) therein, the heater(s) to heat previously-deposited metal in the object region; a molten metal depositor to provide a melt flow through the hole and into the object region; powder introduction unit(s) to deliver an allocated amount of at least one cast-property modifying powder through the hole and into said object region; the holder to hold the molten metal depositor, the heater(s) and the powder introduction unit(s) together in pre-defined locations for combined movement above the top surface.