A method of riveting a first substrate and a second substrate with a rivet includes delivering a first ultrasonic pulse to a respective exterior surface of the first substrate at a predefined target area, via an ultrasonic device. The first ultrasonic pulse is configured to soften the first substrate at a first softening temperature. The method includes attaching a crust layer on a rivet head of the rivet. A second ultrasonic pulse is delivered to the predefined target area to soften the crust layer at a second softening temperature, via the ultrasonic device. A surface profile of the crust layer is fashioned via compression of a horn inner cavity of the ultrasonic device over the crust layer. The crust layer is cooled to harden into a seal configured to prevent entry of moisture between the rivet and the respective exterior surface of the first substrate, thereby reducing galvanic corrosion.

A method of riveting a first substrate and a second substrate with a rivet includes delivering a first ultrasonic pulse to a respective exterior surface of the first substrate at a predefined target area, via an ultrasonic device. The first ultrasonic pulse is configured to soften the first substrate at a first softening temperature. The method includes attaching a crust layer on a rivet head of the rivet. A second ultrasonic pulse is delivered to the predefined target area to soften the crust layer at a second softening temperature, via the ultrasonic device. A surface profile of the crust layer is fashioned via compression of a horn inner cavity of the ultrasonic device over the crust layer. The crust layer is cooled to harden into a seal configured to prevent entry of moisture between the rivet and the respective exterior surface of the first substrate, thereby reducing galvanic corrosion.

Friction stir blind rivet systems and methods are provided for joining workpieces. A FSBR joining system includes a mandrel with a head forming a tip. A stem extends from the head and has a narrowed section forming a notch. A tail section of the mandrel is configured to break off at the notch forming a broken end. A shank also has a head and a body, with a through-hole defined through the shank. The shank head includes a shoulder forming a surface contacting one workpiece. The head has an outermost point opposite the surface. A range is defined between the outermost point of the head and the surface. A wall projects from another workpiece and is formed around the body. The wall has a size formed by the mandrel and that is controlled to enable the body to deform.

Friction stir blind rivet systems and methods are provided for joining workpieces. A FSBR joining system includes a mandrel with a head forming a tip. A stem extends from the head and has a narrowed section forming a notch. A tail section of the mandrel is configured to break off at the notch forming a broken end. A shank also has a head and a body, with a through-hole defined through the shank. The shank head includes a shoulder forming a surface contacting one workpiece. The head has an outermost point opposite the surface. A range is defined between the outermost point of the head and the surface. A wall projects from another workpiece and is formed around the body. The wall has a size formed by the mandrel and that is controlled to enable the body to deform.

A coating applied to an article is provided. The coating has an adhesive material, in contact with at least one substrate of the article. The coating has a plurality of high density metal pellets disposed in the adhesive material. The high density metal pellets are in an amount of at least 90% by weight of the total weight percent of the coating, and each high density metal pellet has a diameter of at least 0.04 inch. The coating further has a polymer material. The coating is applied to the at least one substrate of the article to obtain a mass-enhanced, coated article. The coating has a coating thickness of at least 0.25 inch. The coating thickness and the amount of high density metal pellets are sufficient to provide an attenuation of vibration of the coated article and a reduced risk of unwanted ergonomic effects.

An overlapping part of a first member and a second member is joined using a tool for friction stir spot welding and a rivet. The first member is disposed on a side where the tool is press-fitted first, and the second member is disposed on a side where the tool is press-fitted last, so that the overlapping part is formed. The tool is press-fitted into the overlapping part to perform friction stirring, thereby forming a friction stirred part in the overlapping part. The rivet is press-fitted into the friction stirred part from the first member side.

A joining device includes a nose, a punch, and a die anvil. The punch is coaxially slidable within the nose. A fastener is arranged within the nose and is coaxially slidable within the nose and movable by the punch. An ultrasonic vibration is focused through the die anvil to a zone on a material assembly arranged thereon for heating the zone. The punch is configured to drive the fastener outwardly from the nose and into the material assembly at the zone.

A method of riveting a first substrate and a second substrate with a rivet includes delivering a first ultrasonic pulse to a respective exterior surface of the first substrate at a predefined target area, via an ultrasonic device. The first ultrasonic pulse is configured to soften the first substrate at a first softening temperature. The method includes attaching a crust layer on a rivet head of the rivet. A second ultrasonic pulse is delivered to the predefined target area to soften the crust layer at a second softening temperature, via the ultrasonic device. A surface profile of the crust layer is fashioned via compression of a horn inner cavity of the ultrasonic device over the crust layer. The crust layer is cooled to harden into a seal configured to prevent entry of moisture between the rivet and the respective exterior surface of the first substrate, thereby reducing galvanic corrosion.

A method of riveting a first substrate and a second substrate with a rivet includes delivering a first ultrasonic pulse to a respective exterior surface of the first substrate at a predefined target area, via an ultrasonic device. The first ultrasonic pulse is configured to soften the first substrate at a first softening temperature. The method includes attaching a crust layer on a rivet head of the rivet. A second ultrasonic pulse is delivered to the predefined target area to soften the crust layer at a second softening temperature, via the ultrasonic device. A surface profile of the crust layer is fashioned via compression of a horn inner cavity of the ultrasonic device over the crust layer. The crust layer is cooled to harden into a seal configured to prevent entry of moisture between the rivet and the respective exterior surface of the first substrate, thereby reducing galvanic corrosion.

A power tool has a body, a trigger, a motor, a shaft set, a ball screw, and a pre-fastening module. The pre-fastening module has a first pre-fastening detecting member and a second pre-fastening detecting member. The first pre-fastening detecting member is moved with a connecting shaft of the shaft set in an axial direction. The second pre-fastening detecting member is located on a moving path of the ball screw. When a threaded spindle of the shaft set is inserted in a rivet nut and the connecting shaft is pressed to move inward the body, the first pre-fastening detecting member is moved to align with the second pre-fastening detecting member, and the motor is started automatically to drive the threaded spindle to rotate relative to the rivet nut. The motor will be stopped automatically after the rivet nut is pre-fastened on the threaded spindle, and this is convenient in use.