An object of the present invention is to, while forming a heat insulating layer on a squish area surface of a top surface of a piston main body, prevent generation of large cracks on the heat insulating layer and suppress damages and peeling of the heat insulating layer. To achieve this object, in the present invention, pressure is applied to a heat insulating layer provided on a top surface of a piston main body, that is, a pressing stress is applied to the heat insulating layer in advance.

Disclosed are a cylinder liner for insert casting and a method for manufacturing the same. In particular, the cylinder liner for insert casting has cooling and warming performances suitable for functions of respective parts by imparting multiple layers having different thermal conductivity on the surface of the cylinder liner for insert casting, such that the cylinder liner can be used for vehicle cylinder blocks.

A vehicle internal combustion piston and method of construction thereof are provided. The piston includes piston body extending along a central longitudinal axis, having an upper combustion wall forming an upper combustion surface and an undercrown surface opposite the upper combustion surface. An annular ring belt region depends from the upper combustion surface, a pair of skirt panels depend from the ring belt region, and a pair of pin bosses depend from the undercrown surface to provide laterally spaced pin bores aligned along a pin bore axis for receipt of a wrist pin. The undercrown surface forms a central undercrown surface, and a portion of either an open outer cooling gallery, a sealed outer cooling gallery, or an outer galleryless region, wherein an insulating coating is applied to at least one of the portions of the undercrown surface.

Making a piston includes receiving a piston crown including a combustion face forming a combustion bowl. The piston includes a base material, and a thermal barrier coating (TBC) material forming at least a portion of the combustion face including a bowl edge. Making a piston further includes advancing a polishing tool into contact with the combustion face, spinning the polishing tool such that a positive piston profile is polished via contact with a negative tool profile, and removing some of the TBC material based on the spinning the polishing tool relative to the piston.

Provided are a heat-resistant member provided with a heat-shielding coating suitable for stable manufacturing and excellent in heat-insulating, thermoresponsive and distortion accommodating properties, and a method for manufacturing the same. The heat-shielding coating includes a metallic portion formed of agglomerates of a plurality of metal particles, and inorganic compound particles dispersed in the metallic portion. The metal particles are diffusion-bonded each other, and the metallic portion and a base material of the heat-resistant member are diffusion-bonded each other. The manufacturing method includes the steps of depositing mixed particles of the metal particles and the inorganic compound particles on a surface of the base material in a film shape; resistance-heating the mixed particles by current-passing while pressurized in a thickness direction; diffusion-bonding the metal particles each other; and the metallic portion and the base material each other.

A first angle portion where part of a bearing cap side wall portion is cut out and a second angle portion where part of a bearing cap bottom surface portion is cut out are formed in a region (an angle region of a bearing cap) including a part where respective extension portions of the bearing cap side wall portion and the bearing cap bottom surface portion intersect each other, and a gap is provided between the crankcase side wall portion of a journal wall and the first angle portion and between a crankcase bottom surface portion and the second angle portion.

A piston crown for a piston of a pair of pistons in a two-stroke, opposed-piston, compression ignition combustion engine has a barrier layer and a conductive layer. The barrier layer at least partially surrounds a combustion chamber formed by the piston crown and an end surface of an opposing piston. The conductive layer connects the crown to the rest of the piston body. The barrier layer and the conductive layer are joined either through welding or through the fabrication process. Optionally, the piston crown includes an insulating layer between the barrier and conductive layers.

A bridge member is installed in an opening of a water jacket, and a probe of a friction stir welding tool, which rotates about an axis parallel to a cylinder axis, is pressed against a central part of an upper surface of the bridge member. The probe is kept pressed against the central part of the upper surface for a predetermined time to cause side surfaces of the bridge member to expand and come into contact with both a cylinder wall and an outer wall. The probe is moved from the central part of the upper surface to the outer wall, or the cylinder wall, while the probe is kept pressed against the upper surface, thereby friction-stir welding the outer wall, or the cylinder wall, with the bridge member to each other, and after that, the probe is removed off the top deck.

Described is a crankcase and a method for assembling a multi-part crankcase. The method can include providing a cylinder block and a bearing tunnel upper part. The cylinder block has a plurality of threaded holes into each of which a stud screw is screwed, where the stud screws protrude from the cylinder block. The bearing tunnel upper part has a plurality of through-holes, where each of the through-holes is arranged coaxially to a corresponding stud screw. On a side facing the cylinder head, each of the through-holes has an internal thread having a first direction of rotation. A plurality of threaded sleeves, each threaded sleeve has an internal thread that has a second direction of rotation, an external thread that has a first direction of rotation, and a driver profile for inserting a screwdriver tool in a positive-locking manner, are provided.

In a method for producing a piston, a flat end surface 44a of a rotary tool 44 of a frictional pore sealing device is brought into abutment with the top surface 5a of a low thermal conductivity member 5 cast on the crown surface 2a of an aluminum alloy piston 1, and this rotary tool is pressed against the low thermal conductivity member's side with a load while rotating the rotary tool through an electric motor and a speed reduction mechanism. With this, a frictional heat between the top surface of the low thermal conductivity member and the end surface of the rotary tool causes to form a plastic flow layer 5d on the top surface, thereby sealing an opening portion of a pore 9a on the top surface of the porous member 6.