Abstract: A method for manufacturing hollow and other metal products of irregular shape provides metal powder and binding agent, and the two are feed-mixed and heated to a plastic state. The feed-mix is injected in a mold cavity of a first injection mold to form a first blank, and injected in a mold cavity of a second injection mold to form a second blank. The first blank and the second blank are welded together to form a built-up blank which is degreased to remove the binding agent therein. The degreased built-up blank is sintered to obtain the metal product of irregular shape.

Abstract: A powder feed for injection molding process includes a first metal powder, and a second metal powder. The first metal powder and the second metal powder are mixed together evenly. The second metal powder has a mass percentage of about less than 10% of a total mass of the powder feed for injection molding process. The first metal powder is resistant to the corrosion by a chemical reagent, and the second metal powder is corrodible in the chemical reagent.

Abstract: A method for manufacturing a porous metal with enhanced ability to bond to a plastic subsequently powder feed for injection molding process provides a powder feed to an injection molding process, to form a green embryo. The green embryo is sent into a sintering furnace for high-temperature sintering to obtain a blank sintered product. A chemical reagent is applied to form pores on the sintered product. The powder feed includes first and second metal powders evenly mixed. The second metal powder has a mass percentage of about less than 10% of a total mass of the powder feed for injection molding process. The first metal powder is corrosion-resistant. The second metal powder is readily corrodible.

Abstract: A method of making stainless steel includes smelting metal material and atomizing and powdering the smelted metal material to obtain a first alloy powder, detecting a mass fraction of manganese in the first alloy powder, heating and kneading the first alloy powder with plastic, and granulating, injection molding, and sintering the first alloy powder kneaded with plastic to obtain stainless steel. If the mass fraction of manganese in the first alloy powder is less than 12%, before heating and kneading with plastic, a predetermined amount of manganese-containing material is added to the first alloy powder to obtain a second alloy powder having a mass fraction of manganese of 12-15%.

Abstract: A method for manufacturing a porous metal with enhanced ability to bond to a plastic subsequently powder feed for injection molding process provides a powder feed to an injection molding process, to form a green embryo. The green embryo is sent into a sintering furnace for high-temperature sintering to obtain a blank sintered product. A chemical reagent is applied to form pores on the sintered product. The powder feed includes first and second metal powders evenly mixed. The second metal powder has a mass percentage of about less than 10% of a total mass of the powder feed for injection molding process. The first metal powder is corrosion-resistant. The second metal powder is readily corrodible.

Abstract: A powder injection molding feedstock includes powder particles, a main binder, and a secondary binder. A glass-transition temperature of the secondary binder is greater than a glass-transition temperature of the main binder, the secondary binder coats the powder particles, and the main binder coats the secondary binder and the powder particles.

Abstract: A method for manufacturing a powder injection molding feedstock includes providing a plurality of powder particles and a secondary binder and applying primary kneading in an internal mixer. The primary mixture is cooled and crushed. A main binder is provided and put into the internal mixer to mix with the mixture that being crushed for secondary kneading to obtain the powder injection molding feedstock. Glass-transition temperature of the secondary binder is greater than glass-transition temperature of the main binder. The secondary binder coats the powder particles. The main binder coats the secondary binder and the powder particles.

Abstract: A method for manufacturing metal product having irregular shapes includes steps of providing powder and binding agent, and mixing the powder and binding agent as a mixed feed. The mixed feed is heated to a plastic state, and injected into a mold cavity to form a plurality of blanks. The blanks are degreased to remove the binding agent and are sintered to form workpieces. A substrate or substrates and the workpieces form different parts of the metal product having irregular shapes. The workpieces are disposed on substrate to form a preform and the preform is bonded to form the metal products of irregular shape.

Abstract: A method for manufacturing hollow and other metal products of irregular shape provides metal powder and binding agent, and the two are feed-mixed and heated to a plastic state. The feed-mix is injected in a mold cavity of a first injection mold to form a first blank, and injected in a mold cavity of a second injection mold to form a second blank. The first blank and the second blank are welded together to form a built-up blank which is degreased to remove the binding agent therein. The degreased built-up blank is sintered to obtain the metal product of irregular shape.

Abstract: A method for manufacturing a powder injection molding feedstock includes providing a plurality of powder particles and a secondary binder and applying primary kneading in an internal mixer. The primary mixture is cooled and crushed. A main binder is provided and put into the internal mixer to mix with the mixture that being crushed for secondary kneading to obtain the powder injection molding feedstock. Glass-transition temperature of the secondary binder is greater than glass-transition temperature of the main binder. The secondary binder coats the powder particles. The main binder coats the secondary binder and the powder particles.

Abstract: A fan assembly includes a first fan and a second fan stacked together. Each of the first fan and the second fan includes a frame and a supporting base received in the frame. Several extending portions extend from a bottom of the frame of the first fan. A buckling block is formed on an inner side face of each of the extending portions. Several receiving portions are formed at a top of the frame of the second fan corresponding to the extending portions, respectively. A positioning groove is defined in each of the receiving portions. The buckling blocks are engagingly received in the positioning grooves.

Abstract: A fan assembly includes a first fan and a second fan stacked together. Each of the first fan and the second fan includes a frame and a supporting base received in the frame. Several extending portions extend from a bottom of the frame of the first fan. A buckling block is formed on an inner side face of each of the extending portions. Several receiving portions are formed at a top of the frame of the second fan corresponding to the extending portions, respectively. A positioning groove is defined in each of the receiving portions. The buckling blocks are engagingly received in the positioning grooves.

Abstract: An oil sealing structure of a motor includes a cover and at least one sealing element. The motor has a shaft, a fluid bearing and a bushing. The fluid bearing mounts to the shaft and is accommodated in the bushing. The cover is disposed around the shaft and is connected with an opening of the bushing. The sealing element is disposed around the shaft and between the fluid bearing and the cover. A fan and a motor including the above-mentioned oil sealing structure are also disclosed.

Abstract: An exemplary sleeve bearing system includes a bearing housing, a sleeve bearing and a resilient washer. The bearing housing defines a receiving hole therein. The receiving hole has a first diameter. The sleeve bearing has a second diameter which is slightly less than the first diameter, and the sleeve bearing is received in the receiving hole of the bearing housing. The resilient washer is received in the receiving hole of the bearing housing and is fitted around the sleeve bearing. The resilient washer is sandwiched between the bearing housing and the sleeve bearing and resiliently abuts an outer circumferential surface of the sleeve bearing to thereby mount the sleeve bearing in the receiving hole of the bearing housing.

Abstract: A cooling fan includes a fan housing and a stator and an impeller received in the fan housing. The fan housing includes a frame and a mounting portion located in the frame. The stator is received in the frame and mounted to the mounting portion. The impeller is mounted to the stator and rotatable with respect to the stator. The impeller includes a hub and a plurality of blades extending radially and outwardly from the hub. Each of the blades includes an inner end connected with the hub and an outer end distant from the hub. Each of the blades forms a tab on the outer end at the end surface.

Abstract: A dynamic bearing manufacturing includes steps of: providing a bearing and a processing tool, the bearing having an axial hole, and the processing tool having at least one protruding pattern formed on an exterior wall of the processing tool; positioning the processing tool into the axial hole of the bearing; pressing the processing tool to contact with an inner wall of the bearing so as to transfer and print the protruding pattern of the processing tool onto the inner wall of the bearing; rotating the processing tool at a first rotation speed and driving the bearing to rotate at a second rotation speed; and forming at least one concave pattern on the inner wall of the bearing, and the at least one concave pattern being corresponding to the protruding pattern of the processing tool.

Abstract: A cooling fan includes a fan housing and a stator and an impeller received in the fan housing. The fan housing includes a frame and a mounting portion located in the frame. The stator is received in the frame and mounted to the mounting portion. The impeller is mounted to the stator and rotatable with respect to the stator. The impeller includes a hub and a plurality of blades extending radially and outwardly from the hub. Each of the blades includes an inner end connected with the hub and an outer end distant from the hub. Each of the blades forms a tab on the outer end at the end surface.

Abstract: A sleeve bearing system includes a bearing housing, a sleeve bearing received in the bearing housing, and a wear-resistant pad received at a bottom of the bearing housing. The bearing housing defines a receiving recess therein for receiving the sleeve bearing. The wear-resistant pad is sandwiched between the sleeve bearing and a bottom of the bearing housing. The wear-resistant pad includes a central supporting portion aligning with the bearing hole of the sleeve bearing and a plurality of ears extending radially and outwardly from and an outer periphery of the supporting portion. A reservoir is defined between adjacent ears around the supporting portion.

Abstract: An exemplary sleeve bearing system includes a bearing housing, a sleeve bearing and a resilient washer. The bearing housing defines a receiving hole therein. The receiving hole has a first diameter. The sleeve bearing has a second diameter which is slightly less than the first diameter, and the sleeve bearing is received in the receiving hole of the bearing housing. The resilient washer is received in the receiving hole of the bearing housing and is fitted around the sleeve bearing. The resilient washer is sandwiched between the bearing housing and the sleeve bearing and resiliently abuts an outer circumferential surface of the sleeve bearing to thereby mount the sleeve bearing in the receiving hole of the bearing housing.

Abstract: A cooling fan includes a fan housing and a rotor. The fan housing includes an inner surface defining an inner space therein. The inner surface expands along a direction parallel to a central axis of the fan housing. The rotor is received in the inner space and surrounded by the inner surface of the fan housing. The rotor includes a hub and a plurality of rotary blades extending outwardly from the hub. Each of the rotary blades has an outer edge confronting the inner surface of the fan housing. The outer edge of each rotary blade slants towards the central axis of the fan housing.