Abstract: A method of treating a light metal cylinder bore wall to adherently receive a thermally sprayed metallic coating, that comprises (a) honing the wall to produce a net cylinder shape surface by use of spiral overlapping cross-abrasions having certain peaks and valleys of the abrasions folded over and molded to create tears, folds and undercuts rendering a hook and ladder effect, the honing being carried out with the use of a machining coolant to prevent burnishing of the walls; (b) either concurrently or shortly after step (a), washing the honed surface with a hot alkaline solution comprising (i) a non-soaping aluminate forming agent (sodium xanthate) that produces a residue on the walls, and (ii) surfactants that facilitate wetting of the walls even when some steam bubbles may be present; (c) rinsing the washed surfaces without disturbing the residue; and (d) thermally spraying a metallic bond coat and top coat on the honed and washed surface to render adhesion between the coating and prepared surface that is

Abstract: A method of preparing and coating cylindrical bore surfaces of an aluminum workpiece that comprises (a) inserting and rotationally reciprocally moving a plurality of honing elements against the bore surface with a pressure of at least 30 psi to effect a pattern of spiral overlapping abrasions on said surface, each element being constituted of multifaceted, irregular-shaped, abrasive particles (i.e., diamond or SiC) having a particle size of 30-1300 micrometers. The particles, when in contact with the surface, plow micro-sized, non-smooth and irregularly spaced grooves in the aluminum workpiece resulting in spiral peaks and valleys along the direction of movement of the particles, whereupon repeated reciprocation and rotation of the elements (i.e.

Abstract: Apparatus (10) and a method for finishing a workpiece (12) are performed by a first spindle (24) that rotatably mounts a milling cutter (28) about a central axis A and a second spindle (32) also mounted on the support for rotation about the central axis A to mount a grinding wheel. The first spindle (24) has an annular shape that extends around the second (32), and the apparatus includes a drive (38) capable of rotating the first spindle (24) at a slower rate than the rotation of the second spindle (32) such that milling and grinding operations can be performed at effective speeds. An axial slide (40) mounts the first spindle (24) for rotation and for axial movement along the central axis with the second spindle (32) on which the grinding wheel (36) is mounted located within the annular support.

Abstract: A segmented broach bar for machining axially separated coaxial bearing bores contained within a component for an internal combustion engine includes axially separated pilot segments and axially separated broaching segments, with at least one of the pilot segments being positioned between a pair of broaching segments. A broach bar has a lead end which first engages the bearing bores, with the broaching and pilot segments having diameters which are sized progressively greater as the distance from the lead end increases, with the broach and pilot segments being sized such that each broach segment produces a bore diameter accommodating the immediately following pilot segment.

Abstract: A drill construction to overcome the problem of high speed (>5000 rpm), high feed rate (>200 inches/minute) chip removal in deep hole drilling of nonferrous workpieces, comprising: (a) a shank for receiving rotary power, (b) an elongate bit extending from such shank coaxially aligned therewith and having a continuous single spiral land occupying one quadrant or less of said bit cross-section with a single spiral flute surrounding said land; (c) a cutting end portion extending integrally from said bit, said end portion having a conically-shaped end surface interrupted by diametrically opposed flutes, one of said flutes being a continuation of the bit flute thereby to define cutting edges, said edges further being defined by arcuate indentations resulting in a plurality of cusps to assist in breaking chips as they are formed; and (d) channels for conducting high pressure (>800 psi) fluid for cooling the bit, end portion, and chips during drilling and for hydrodynamically forcing the broken chips along

Abstract: An internal combustion engine which is provided with a cylinder head structure possessing truer finished surfaces and which incorporates unsmeared porosity in such surfaces to act as reservoirs for lubrication; as a result the design gap with the valve stem can be closer for improved lubrication.

Abstract: A method for fabricating an internal combustion engine cylinder head, comprises the steps: (a) forming a cast cylinder head with a passage having implanted in the walls of such passage a valve stem guide sleeve insert and a valve seat insert, the inserts being formed of fused powder metal and each having an internal cylindrical surface prepared to near net shape no longer requiring macroscale sizing; and (b) microsizing both of the internal cylindrical surfaces by a single pass of a common rotary abrasive tool inflexible along its axis and supported for accurate alignment independent of the guide sleeve. The cylinder head may be first formed with such passage having a recess for a valve seat insert and a guide bore for a guide sleeve; preshaped inserts are then press-fit into such recess and guide bore. Near net shape means an overside tolerance of plus 0.002-0.003 inches; macroscale means measurements in increments or units greater than 0.01 inches.