In various embodiments, three-dimensional layered metallic parts are substantially free of gaps between successive layers, are substantially free of cracks, and have densities no less than 97% of the theoretical density of the metallic material.

A method of spot welding a workpiece stack-up that includes a steel workpiece and an aluminum alloy workpiece involves passing an electrical current through the workpieces and between welding electrodes that are constructed to affect the current density of the electrical current. The welding electrodes, more specifically, are constructed to render the density of the electrical current greater in the steel workpiece than in the aluminum alloy workpiece. This difference in current densities can be accomplished by passing, at least initially, the electrical current between a weld face of the welding electrode in contact with the steel workpiece and a perimeter region of a weld face of the welding electrode in contact with the aluminum alloy workpiece.

A spot welding system includes a spot welding gun, a robot, and a tip dresser that polishes a face of electrode. The tip dresser includes a blade that cuts the face of the electrode and a blade driving motor that rotates the blade. A dresser control section of a control device detects torque of the blade driving motor. When the torque of the blade driving motor exceeds a predetermined torque upper limit value, the dresser control section carries out speed reduction control that reduces the rotation speed of the blade driving motor.

Provided is a high-temperature object observation device including a camera capable of acquiring an image of an observation region adjacent to a heat source and a light shielding device. In the high-temperature object observation device, a light shielding device includes a light shielding part that covers the vicinity of the heat source, a holding object that holds the heat source at a position exposed from the light shielding part, and an actuator that releases engagement of the holding object, and immediately after the light shielding device is brought into operation and the heat source is covered with the light shielding part, the camera acquires an image of the observation region.

Provided is a high-temperature object observation device including a camera capable of acquiring an image of an observation region adjacent to a heat source and a light shielding device. In the high-temperature object observation device, a light shielding device includes a light shielding part that covers the vicinity of the heat source, a holding object that holds the heat source at a position exposed from the light shielding part, and an actuator that releases engagement of the holding object, and immediately after the light shielding device is brought into operation and the heat source is covered with the light shielding part, the camera acquires an image of the observation region.

An example welding-type system includes: a welding-type power source configured to provide welding-type current to a welding-type circuit, the welding-type circuit comprising a welding-type electrode and a first contact tip of a welding torch; an electrode preheating circuit configured to provide preheating current through a first portion of the welding-type electrode via a second contact tip of the welding torch; a switching circuit configured to control a current flow between the welding-type power source and the first contact tip; and a preheat control circuit configured to control the switching circuit to: selectively direct current from the welding-type power source to the second contact tip; and selectively divert current from the electrode preheating circuit to the first contact tip

An example welding-type system includes: a welding-type power source configured to provide welding-type current to a welding-type circuit, the welding-type circuit comprising a welding-type electrode and a first contact tip of a welding torch; an electrode preheating circuit configured to provide preheating current through a first portion of the welding-type electrode via a second contact tip of the welding torch; a switching circuit configured to control a current flow between the welding-type power source and the first contact tip; and a preheat control circuit configured to control the switching circuit to: selectively direct current from the welding-type power source to the second contact tip; and selectively divert current from the electrode preheating circuit to the first contact tip.

An example welding-type system includes: a welding-type power source configured to provide welding-type current to a welding-type circuit, the welding-type circuit comprising a welding-type electrode and a first contact tip of a welding torch; an electrode preheating circuit configured to provide preheating current through a first portion of the welding-type electrode via a second contact tip of the welding torch; a switching circuit configured to control a current flow between the welding-type power source and the first contact tip; and a preheat control circuit configured to control the switching circuit to: selectively direct current from the welding-type power source to the second contact tip; and selectively divert current from the electrode preheating circuit to the first contact tip.

A contact tip assembly with a preheating tip comprises a welding-type power source configured to provide welding-type current to a welding-type circuit, the welding-type circuit comprising a welding-type electrode and a first contact tip of a welding torch; an electrode preheating circuit configured to provide preheating current through a first portion of the electrode via a second contact tip of the welding torch; and a preheat controller to: monitor a voltage drop across a second portion of the electrode; adjust at least one of the welding-type current or the preheating current based on the voltage drop, the second portion of the electrode comprising at least part of the first portion of the electrode; and control the preheating current based on a hydrogen reduction goal and based on stored parameters associated with a type of the electrode, a chemistry of the electrode, or a wire size.

A contact tip assembly with a preheating tip comprises a welding-type power source configured to provide welding-type current to a welding-type circuit, the welding-type circuit comprising a welding-type electrode and a first contact tip of a welding torch; an electrode preheating circuit configured to provide preheating current through a first portion of the electrode via a second contact tip of the welding torch; and a preheat controller to: monitor a voltage drop across a second portion of the electrode; adjust at least one of the welding-type current or the preheating current based on the voltage drop, the second portion of the electrode comprising at least part of the first portion of the electrode; and control the preheating current based on a hydrogen reduction goal and based on stored parameters associated with a type of the electrode, a chemistry of the electrode, or a wire size.