With the method according to the invention, mould parts for casting moulds for light metal casting can be treated such that the danger of crack formation in the region of the surface sections of the mould part coming into contact with the light metal melt during casting is reduced to a minimum. This is achieved in that by means of nitriding treatment on the mould part a nitride-hardened edge layer adjoining its free surface is generated which is harder than the inner core region of the mould part and comprises a diffusion layer adjoining the core region and a compound layer located on the diffusion layer and adjoining the free surface of the mould part and in that at least one section of the surface of the mould part is mechanically processed by machine hammer peening, in the case of which a hammer tool, which, at a certain impact frequency, carries out an impact movement along a movement axis which is aligned in relation to the free surface at a certain acute angle, is guided continuously over the free surface of the mould part following a track determined in a preceding design step such that the compound layer is removed by the impacting stress in the impact region of the hammer tool.

An investment casting process for manufacturing a cast component is provided. The investment casting process includes forming a core, casting the cast component about the core such that a core positioning feature provides a location of an anticipated pilot hole in the cast component, removing the core from the cast component once the casting is completed, locating, forming and sizing a pilot hole to form a resized pilot hole that can receive a sealing plug and installing the sealing plug into the resized pilot hole.

The present invention relates to a steel for mold, containing: 0.28 mass %≤C≤0.65 mass %, 0.01 mass %≤Si≤0.30 mass %, 1.5 mass %≤Mn≤3.0 mass %, 0.5 mass %≤Cr≤1.4 mass %, 1.9 mass %≤Mo+W/2≤4.0 mass %, 0.2 mass %≤V≤1.0 mass %, and 0.01≤N≤0.10 mass %, with the balance being Fe and inevitable impurities, in which, in a state after quenching and tempering, the steel has: a (Mo, W) carbide having a diameter of 0.2 μm or less being in an amount of 1.2 mass % or more, a ratio (mass ratio) of the amount of the (Mo, W) carbide to an amount of a Cr carbide being 11 or more, and a hardness change of 15 HRC or less.

A sludge digester including a vessel and floating cover. The vessel includes a sidewall and an interior volume configured to receive and contain sludge. According to one embodiment, the cover comprises a frame structure that is constructed and arranged to form a skirt member formed at a periphery of the cover and extending downwardly into the vessel, and a continuous ballast ring attached to a lower portion of the skirt member and configured to form a trough member with an interior surface of the skirt member. The sludge digester may also include a guide system coupled to the sidewall and the skirt member and configured to allow vertical displacement of the cover with change in volume of at least one of a gas and a sludge contained in the vessel beneath the cover.

Provided are a method for preparing a microfluidic device, a microfluidic device and a microfluidic system. The method includes: providing a mold having a groove; injecting a liquid metal into the groove of the mold, and solidifying the liquid metal to obtain a solid metal; separating the solid metal from the mold; providing the solid metal with an electrode; providing a cladding layer on a surface of the solid metal provided with the electrode, such that the solid metal is wrapped by the cladding layer, and at least a part of the electrode extends outside the cladding layer, so as to obtain a preform; and fixing the preform in a substrate, melting the solid metal and extending at least a part of the electrode outside the substrate, to obtain the microfluidic device.

An additive layer manufactured hot work tool according to the present disclosure includes a component composition of by mass %, C: 0.3-0.5% to Si: 2.0% or less, Mn: 1.5% or less, P: 0.05% or less, S: 0.05% or less, Cr: 3.0 to 6.0%, 1 or 2 kinds of compounds of Mo and W, a relation between Mo and W being represented by a relational expression of (Mo+1/2W): 0.5 to 3.5%, V: 0.1 to 1.5%, Ni: 0 to 1.0%, Co: 0 to 1.0%, and Nb: 0 to 0.3%, and with Fe and an unavoidable impurity as a remainder, and an area ratio of defects having an area of 1 m.sup.2 or more is 0.6% or less in a cross section parallel to the amination direction.

A mold device is capable of producing a member formed from aluminum, and includes a mold and a molten metal supply part. The mold is capable of forming a cavity into which molten aluminum is charged. The mold has a base part formed from iron and a surface layer part. The surface layer part is provided on the cavity side of the base part and contains 20 weight % or more of chromium. A dichromium trioxide film is formable on a surface of the cavity side of the surface layer part. The molten metal supply part is capable of supplying molten aluminum into the cavity.

A method for die casting a metal alloy in a cavity, implementing a mold comprising an induction heater to heat the molding surfaces of the cavity. The cavity is filled with the metal alloy by injection and preheated to a nominal preheating temperature T1. The metal in the cavity is solidified. The mold is opened and the part is ejected therefrom. The molding surfaces of the cavity are heated by induction while the part is no longer in contact with said surfaces. The molding surfaces of the cavity are sprayed, the mold being opened, by a release agent. The mold is closed and the cavity is heated the temperature T1.

With the method according to the invention, mould parts for casting moulds for light metal casting can be treated such that the danger of crack formation in the region of the surface sections of the mould part coming into contact with the light metal melt during casting is reduced to a minimum. This is achieved in that by means of nitriding treatment on the mould part a nitride-hardened edge layer adjoining its free surface is generated which is harder than the inner core region of the mould part and comprises a diffusion layer adjoining the core region and a compound layer located on the diffusion layer and adjoining the free surface of the mould part and in that at least one section of the surface of the mould part is mechanically processed by machine hammer peening, in the case of which a hammer tool, which, at a certain impact frequency, carries out an impact movement along a movement axis which is aligned in relation to the free surface at a certain acute angle, is guided continuously over the free surface of the mould part following a track determined in a preceding design step such that the compound layer is removed by the impacting stress in the impact region of the hammer tool.

A sludge digester including a vessel and floating cover. The vessel includes a sidewall and an interior volume configured to receive and contain sludge. According to one embodiment, the cover comprises a frame structure that is constructed and arranged to form a skirt member formed at a periphery of the cover and extending downwardly into the vessel, and a continuous ballast ring attached to a lower portion of the skirt member and configured to form a trough member with an interior surface of the skirt member. The sludge digester may also include a guide system coupled to the sidewall and the skirt member and configured to allow vertical displacement of the cover with change in volume of at least one of a gas and a sludge contained in the vessel beneath the cover.