Abstract: The disclosure relates to additive manufacturing processes generally including forming a green part, pre-sintering or debinding the green part, and fully sintering the part. The green part generally includes a solid polymer matrix or layers with metal particles therein. A debinding or pre-sintering process can include a controlled-temperature and/or controlled-heating rate debinding step to decompose the polymer binder and simultaneously the pre-sinter the metal particles in the desired shape. A sintering process can include a two-step heating process at different temperatures to provide high-density components without shape deformation. Debinding and sintering can be performed in a co-debinding/co-sintering process to form a single pre-sintered part, which then can be fully sintered to provide a final part with a complex geometry. The resulting parts exhibit better dimensional stability, higher-density, and are defect and carbide free.

Abstract: The disclosure relates to cubic boron nitride inserts for machining iron-based workpieces, as well as related methods and apparatuses. The insert includes a cutting element containing cubic boron nitride (cBN) in an amount in a range of 50 wt. % to 95 wt. % based on the cutting element, and a binder containing at least one of (i) alumina (Al2O3) and a manganese material (e.g., an oxide such as MnOx) and (ii) zirconia (ZrO2). The insert can be used for various machining processes, for example turning or boring. Suitable workpieces include iron-based materials or ferrous alloys, for example a cast iron such as compacted graphite iron (CGI).

Abstract: The disclosure relates to a method for forming a metal article by additive manufacturing and related apparatus for performing the method. A metal particle suspension including a UV-curable polymeric resin liquid medium, and metal particles distributed throughout the liquid medium is deposited and cured by spatially selective exposure to UV radiation in a layer-by-layer process. Metal particle size can be selected in combination with the applied layer thickness to ensure complete cure throughout the applied layer while providing a high print speed and high spatial resolution. Intermittent or periodic partial curing of an applied layer can be used to maintain a homogeneous distribution of metal particles in the applied layer prior to full curing. The final product is achieved after sintering, which removes the cured binder in a debinding step and also provides the desired final article at close to the full density.

Abstract: The disclosure relates to sintering compositions that can be used in three-dimensional printing or additive manufacturing processes. The sintering compositions generally include one or more metallic iron-containing powders and a minor amount of a boron-containing powder as a sintering aid. Sintered models or products formed from the sintering compositions have substantially improved density and surface roughness values relative to models formed without the boron-containing powder.

Abstract: The disclosure relates to microchemical (or microfluidic) apparatus as well as related methods for making the same. The methods generally include partial sintering of sintering powder (e.g., binderless or otherwise free-flowing sintering powder) that encloses a fugitive phase material having a shape corresponding to a desired cavity structure in the formed apparatus. Partial sintering removes the fugitive phase and produces a porous compact, which can then be machined if desired and then further fully sintered to form the final apparatus. The process can produce apparatus with small, controllable cavities shaped as desired for various microchemical or microfluidic unit operations, with a generally smooth interior cavity finish, and with materials (e.g., ceramics) able to withstand harsh environments for such unit operations.

Abstract: The disclosure relates to brush compositions for magnetic field-assisted finishing (MAF). In particular, the disclosure relates to brush compositions for MAF including a carrier fluid, optionally a solid lubricant dispersed in the carrier fluid, abrasive particles dispersed in the carrier fluid, and magnetic particles dispersed in the carrier fluid. The solid lubricant can be in the form of solid lubricant nanoplatelets or other nanoparticles. The disclosure also relates to systems, methods, and uses of the brush composition.

Abstract: The disclosure relates to a method for forming a metal article by additive manufacturing and related apparatus for performing the method. A metal particle suspension including a UV-curable polymeric resin liquid medium, and metal particles distributed throughout the liquid medium is deposited and cured by spatially selective exposure to UV radiation in a layer-by-layer process. Metal particle size can be selected in combination with the applied layer thickness to ensure complete cure throughout the applied layer while providing a high print speed and high spatial resolution. Intermittent or periodic partial curing of an applied layer can be used to maintain a homogeneous distribution of metal particles in the applied layer prior to full curing. The final product is achieved after sintering, which removes the cured binder in a debinding step and also provides the desired final article at close to the full density.

Abstract: The disclosure relates to sintering compositions that can be used in three-dimensional printing or additive manufacturing processes. The sintering compositions generally include one or more metallic iron-containing powders and a minor amount of a boron-containing powder as a sintering aid. Sintered models or products formed from the sintering compositions have substantially improved density and surface roughness values relative to models formed without the boron-containing powder.

Abstract: The disclosure relates to sintering compositions that can be used in three-dimensional printing or additive manufacturing processes. The sintering compositions generally include one or more metallic iron-containing powders and a minor amount of a boron-containing powder as a sintering aid. Sintered models or products formed from the sintering compositions have substantially improved density and surface roughness values relative to models formed without the boron-containing powder.

Abstract: The disclosure relates to cubic boron nitride inserts for machining iron-based workpieces, as well as related methods and apparatuses. The insert includes a cutting element containing cubic boron nitride (cBN) in an amount in a range of 50 wt. % to 95 wt. % based on the cutting element, and a binder containing at least one of (i) alumina (Al2O3) and a manganese material (e.g., an oxide such as MnOx) and (ii) zirconia (ZrO2). The insert can be used for various machining processes, for example turning or boring. Suitable workpieces include iron-based materials or ferrous alloys, for example a cast iron such as compacted graphite iron (CGI).

Abstract: The disclosure relates to microchemical (or microfluidic) apparatus as well as related methods for making the same. The methods generally include partial sintering of sintering powder (e.g., binderless or otherwise free-flowing sintering powder) that encloses a fugitive phase material having a shape corresponding to a desired cavity structure in the formed apparatus. Partial sintering removes the fugitive phase and produces a porous compact, which can then be machined if desired and then further fully sintered to form the final apparatus. The process can produce apparatus with small, controllable cavities shaped as desired for various microchemical or microfluidic unit operations, with a generally smooth interior cavity finish, and with materials (e.g., ceramics) able to withstand harsh environments for such unit operations.

Abstract: The disclosure relates to microchemical (or microfluidic) apparatus as well as related methods for making the same. The methods generally include partial sintering of sintering powder (e.g., binderless or otherwise free-flowing sintering powder) that encloses a fugitive phase material having a shape corresponding to a desired cavity structure in the formed apparatus. Partial sintering removes the fugitive phase and produces a porous compact, which can then be machined if desired and then further fully sintered to form the final apparatus. The process can produce apparatus with small, controllable cavities shaped as desired for various microchemical or microfluidic unit operations, with a generally smooth interior cavity finish, and with materials (e.g., ceramics) able to withstand harsh environments for such unit operations.

Abstract: The disclosure relates to microchemical (or microfluidic) apparatus as well as related methods for making the same. The methods generally include partial sintering of sintering powder (e.g., binderless or otherwise free-flowing sintering powder) that encloses a fugitive phase material having a shape corresponding to a desired cavity structure in the formed apparatus. Partial sintering removes the fugitive phase and produces a porous compact, which can then be machined if desired and then further fully sintered to form the final apparatus. The process can produce apparatus with small, controllable cavities shaped as desired for various microchemical or microfluidic unit operations, with a generally smooth interior cavity finish, and with materials (e.g., ceramics) able to withstand harsh environments for such unit operations.

Abstract: The disclosure relates to sintering compositions that can be used in three-dimensional printing or additive manufacturing processes. The sintering compositions generally include one or more metallic iron-containing powders and a minor amount of a boron-containing powder as a sintering aid. Sintered models or products formed from the sintering compositions have substantially improved density and surface roughness values relative to models formed without the boron-containing powder.

Abstract: A lubricant composition is disclosed that includes (a) a machining oil and (b) an exfoliated graphite nanoparticle (EGN) material stably dispersed in the machining oil. The lubricant composition is a stable suspension and is suitable for use as a liquid lubricant in a Minimum Quantity Lubrication (MQL) process. In the MQL process, the lubricant composition is applied/transferred to a worksite in the form of a mist. The presence of the EGN material in the lubricant composition provides high-temperature stability and lubricity under MQL conditions. A very small amount is transferred especially at high cutting speeds where the mist of the machining oil evaporates, but the EGN material remains on the surface to provide lubricity. Any operation involving machining can benefit from this lubricant composition. The method provides important benefits of reducing chipping on cutting tools and providing the additional lubricity especially when the cutting become very hot and thus extending tool life.

Abstract: A lubricant composition is disclosed that includes (a) a machining oil and (b) an exfoliated graphite nanoparticle (EGN) material stably dispersed in the machining oil. The lubricant composition is a stable suspension and is suitable for use as a liquid lubricant in a Minimum Quantity Lubrication (MQL) process. In the MQL process, the lubricant composition is applied/transferred to a worksite in the form of a mist. The presence of the EGN material in the lubricant composition provides high-temperature stability and lubricity under MQL conditions. A very small amount is transferred especially at high cutting speeds where the mist of the machining oil evaporates, but the EGN material remains on the surface to provide lubricity. Any operation involving machining can benefit from this lubricant composition. The method provides important benefits of reducing chipping on cutting tools and providing the additional lubricity especially when the cutting become very hot and thus extending tool life.