A furnace for the heat treatment of a metal product includes constitutive elements, each having a thermal inertia property determined from physical parameters. The constitutive elements include walls delimiting at least partially the furnace, a heating unit for heating the metal product, and a rapid heating element for heating the metal product. The furnace also includes a control circuit for controlling the heating unit and/or the rapid heating element, based on one or more thermal inertia properties of one or more constitutive elements of the furnace, and at least based on a ground of a constitutive element of said furnace.

A microwave heating method using a microwave, including: controlling a frequency of the microwave, to form a single-mode standing wave; disposing an object to be heated in a magnetic field region where a strength of a magnetic field formed by the single-mode standing wave is uniform and maximum; and heating the object to be heated by magnetic heat generation by magnetic loss caused by an action of the magnetic field of the magnetic field region, and/or induction heating by an induced current generated in the object to be heated due to the magnetic field of the magnetic field region.

A workpiece conveyance jig, which is formed of a threaded shaft made of a ceramic, includes an inner member, which is formed of a solid shaft having a constant diameter, and is configured to receive a rotational driving force, and an outer member, which has a hollow shaft-like shape, has a helical protrusion, and is mounted on an outer periphery of the inner member so as to be rotatable integrally with the inner member. The outer member includes a plurality of cylindrical bodies arranged in a row in an axial direction of the workpiece conveyance jig, and has a convex and concave fitting portion formed between two adjacent ones of the plurality of cylindrical bodies, which is configured to engage the two adjacent cylindrical bodies with each other in a direction of rotation of the inner member.

An induction heating device for a metal strip, including: an induction coil provided on one side or on both sides of a front face side or a reverse face side of a metal strip, and that induces an induction current in the strip when a primary current is passed through the coil, the induction current configuring a closed loop as viewed from a direction perpendicular to a metal strip face; plural magnetic cores disposed at a specific position, this being a position at a back face side of the coil and separated from the strip by a specific distance, to concentrate magnetic flux generated by the coil in the strip; and a moving mechanism coupled to the magnetic cores, and that moves the cores to increase or decrease a disposed number of the cores at the specific position disposed side-by-side along a metal strip width direction.

A microwave heating method using a microwave, including: controlling a frequency of the microwave, to form a single-mode standing wave; disposing an object to be heated in a magnetic field region where a strength of a magnetic field formed by the single-mode standing wave is uniform and maximum; and heating the object to be heated by magnetic heat generation by magnetic loss caused by an action of the magnetic field of the magnetic field region, and/or induction heating by an induced current generated in the object to be heated due to the magnetic field of the magnetic field region.

A furnace for the heat treatment of a metal product includes constitutive elements, each having a thermal inertia property determined from physical parameters. The constitutive elements include walls delimiting at least partially the furnace, a heating unit for heating the metal product, and a rapid heating element for heating the metal product. The furnace also includes a control circuit for controlling the heating unit and/or the rapid heating element, based on one or more thermal inertia properties of one or more constitutive elements of the furnace, and at least based on a ground of a constitutive element of said furnace.

A workpiece conveyance jig, which is formed of a threaded shaft made of a ceramic, includes an inner member, which is formed of a solid shaft having a constant diameter, and is configured to receive a rotational driving force, and an outer member, which has a hollow shaft-like shape, has a helical protrusion, and is mounted on an outer periphery of the inner member so as to be rotatable integrally with the inner member. The outer member includes a plurality of cylindrical bodies arranged in a row in an axial direction of the workpiece conveyance jig, and has a convex and concave fitting portion formed between two adjacent ones of the plurality of cylindrical bodies, which is configured to engage the two adjacent cylindrical bodies with each other in a direction of rotation of the inner member.

A method for heat-treating a metal strip, where the metal strip is pre-heated continuously in a pre-heating zone with the aid of hot gas and subsequently undergoes further heat treatment in a directly fired furnace in a reducing and/or oxidizing atmosphere. The metal strip is pre-heated in the pre-heating zone with hot inert gas and further heated with an electric heating system before entering the directly fired furnace. A furnace plant for implementing the process and a related heat recovery system are also disclosed.

Provided is a hot stamping method for manufacturing high strength vehicle body parts. The hot stamping method includes: high frequency induction heating a blank in a first heating furnace while transferring the blank; heating the heated blank to an austenitization temperature or more of a corresponding blank while transferring the heated blank from the first heating furnace to a second heating furnace; and drawing the blank heated to the austenitization temperature or more in the second heating furnace to form and cool the blank by using a press forming apparatus. According to the hot stamping method, it is possible to achieve excellent productivity and reduce energy.

The invention relates to a device for inductively heating at least one workpiece, in particular a substantially strip-shaped workpiece, including at least one furnace housing; at least one inductor arrangement arranged within the furnace housing, the inductor arrangement being arranged at least partially in an inductor region of the furnace housing; at least one heating region for receiving process gas. The heating region being arranged within the furnace housing; and separating material for separating, in particular for thermally separating, the inductor region and the heating region. Furthermore, the invention relates to a method for inductively heating at least one workpiece.