Friday, November 4, 2016
This year Graphitestore is proudly sponsoring MASA, a student rocketry team at the University of Michigan, in the development of a hybrid rocket.
MASA has spent the last three years developing this hybrid rocket, and were in need of graphite for nozzle construction. Graphitestore has donated High-Density, Superfine, Isomolded rods to assist in their design.
These premium quality superfine isomolded rods can be used in applications requiring superior strength and density, and can be viewed under Plates/Rods/Tubes here; each item features a product data sheet and common applications for further information. Please contact us with any questions or custom inquiries.
Monday, June 13, 2016
Graphitestore has developed a new version if its popular “fuel cell” impervious grade FC-GR.
The new grade FCGR-347B consists of specially developed “base grade” with uniformed capillary matrix and improved resin system with higher viscosity for deeper resin penetration
and better chemical resistance. These improvements allow us to produce impervious graphite plates of larger cross-section and thickness up to 1.5”.
These new products can be viewed under our Fuel cell components; each item features a brochure and comparison table for further information.
Please contact us with any questions or custom inquiries
Friday, April 14, 2016
Graphitestore is expanding its pyrolytic graphite discs and plates which are now available in three different materials:
Substrate Nucleated (PG-SN), Continuously Nucleated (PG-CN), and High Conductivity Substrate Nucleated (PG-HT).
Continuously Nucleated (PG-CN) material has physical properties 15-20% higher than that of Substrate Nucleated.
That is why PG-CN is preferred when the application requires a higher compression load. Uses range across metal processing, closed die forging, electronics, or aerospace applications.
The Substrate Nucleated – High Conductivity (PG-HT) grade is similar to Substrate Nucleated (SN) grade of pyrolytic graphite but is thermally annealed to increase thermal conductivity.
The increase in conductivity is about four times that of PG-SN grade or more than four times better than copper.
These new products can be viewed under our pyrolytic graphite; each item features a brochure and comparison table for further information.
Please contact us with any questions or custom inquiries
Monday, November 9, 2015
Graphitestore is expanding its Fuel cell components category by introducing
carbon cloth and
carbon paper products.
Referred to as Gas Diffusion Layers (GDL), these materials are commonly used as key components in various types of fuel cells, including Proton Exchange Membrane (PEM),
Direct Methanol (DMFC) and Phosphoric Acid (PAFC) stacks. In fuel cells these thin, porous sheet must provide high electrical and thermal conductivity and chemical / corrosion
resistance, in addition to controlling the proper flow of reactant gases (hydrogen and air) and managing the water transport out of the membrane electrode assembly (MEA).
This layer must also have controlled compressibility to support the external forces from the assembly, and not deform into the bi-component plate channels to restrict flow.
These new products can be viewed under our Fuel cell components; each item features a brochure and comparison table for further information.
Please contact us with any questions or custom inquiries
Tuesday, May 5, 2015
Graphitestore.com is expanding its selection of CFC (Carbon-Carbon) products with new Threaded Rods & Nuts, U & L Channels, and Plates available in a variety of sizes. CFC parts are lightweight, carbon fiber reinforced, high temperature treated composites. Composed of a fiber reinforced composite material in a carbon matrix they offer superior strength and fracture resistance compared with graphite. CFC (Carbon-Carbon) also exhibits great resistance from heat, oxidation, thermal shock, and excellent chemical corrosion resistance.
CFC (Carbon-Carbon) Plates are now available in GS-CFC400 Grade, featuring chopped fiber in a 2D random fiber alignment. This grade has high interlaminar shear strength, displays in-plane isotropy and is stable to 3600F (2000C). These plates can be precisely machined to specifications. Along with plates, CFC (Carbon-Carbon) Threaded Rods and Nuts are available in this grade in various diameters.
CFC (Carbon-Carbon) U and L Channels have also been added in GS-CFC200 Grade, featuring continuous fiber in a 0°/90° fiber alignment. This material has very high tensile strength and modulus while stable to 3600F (2000C).
All of these attributes make CFC material a superior choice for a variety of components and applications. These include: furnace linings/racks/fixtures, insulation fasteners, sleeves, fans, biomedical devices, aerospace parts, specialized racing brakes and clutches, heating elements, sintering trays and boats, and hardware for metal forming and glass making.
Email email@example.com for any questions on custom machining or inquiries on sizes not seen on our site.
Tuesday, September 3, 2013 – Graphitestore.com has now added two new product lines to its expanding catalogue:
CFC (Carbon-Carbon) Plate and Flexible Graphite Foil.
CFC (Carbon-Carbon) Plates are lightweight, carbon fiber reinforced, high temperature treated composites.
These parts offer superior strength and fracture resistance compared with graphite, while and GRADE GSHD provides great oxidation resistance
and high thermal conductivity while being stable to 3600F (2000C).
Some popular applications for CFC (Carbon-Carbon) Plate are heat treating, sintering trays, powder metallurgy, metal injection molding, atmosphere and vacuum furnaces, furnace racks and fixtures, high temp fasteners, aerospace parts, alternative energy and clutches. Please see our full product description of Flexible Graphite Foil in our catalogue for additional functions and applications.
Flexible graphite foil is made from exfoliated graphite flake and is produced through an extensive calendaring process to give a thin flexible material with no binder or resins. It holds properties such as thermal stability, impermeability, high and low temperature-resistance and corrosion resistance.
Some popular applications for Flexible Graphite Foil products are gaskets used in flanges, level meters, release foils in glassworks and hot presses, backing strips for welding operations, cathodes for electrolysis of liquids, electrical contacts, vessel linings and coatings against hot aggressive media and facing for hot pressing molds. Please see our full product description of Flexible Graphite Foil in our catalogue for additional functions and applications.
Monday, April 8, 2013 -- In response to a high demand for low permeability graphite used in bi-polar plates, we have developed a new resin-filled
Impervious Graphite grade FC-GR. This grade combines the best properties of graphite:
high electrical and thermal conductivity, chemical resistance and easy machining with the low permeability of molded composites. These new plates are intended for
low to mid-temperature fuel cells up to 500°F. For higher temperature fuel cells we recommend using
our Standard Graphite Plates.
Thursday, November 8, 2012 -- GraphiteStore.com now added
Carbon Fiber Composite (CFC)
parts to its catalogue. Carbon Fiber Composites are lightweight, carbon fiber reinforced, high temperature treated composites.
They offer superior strength and fracture resistance compared with graphite. The three types of CFC parts offered are:
Carbon Composite (C-C, CFC) Channels
Carbon Composite (C-C, CFC) Threaded Rods and Nuts
Due to their greater strength and resistance to high temperatures they are often utilized in: heat treating, racks and fixtures,
load plates, vacuum furnace and insulation fastening furniture, aerospace, alternative energy, windmill blades, glass industry,
bottling fixtures, brake linings, heat shields, heating elements, and x-ray targets.
Friday, February 24, 2012 -- GraphiteStore.com is pleased to announce that we have moved
our corporate office to a new location:
160 Lexington Drive
Buffalo Grove, IL 60089
This move has allowed us to consolidate our sales, engineering and distribution into one convenient location.
We aim to better serve you with enhanced customer service and expedited order processing and delivery.
We will continue to have the same phone, fax and email information.
Thursday, December 29, 2011 -- GraphiteStore.com in cooperation with Asbury Carbons, Inc is introducing
nano-particle sized graphite powders.
These powders are composed of ultra-fine particles with a size distribution of 0.10 microns to 20 microns.
The new powders featured are:
GS-2299 nano-Graphite Powder (Nominal BET Surface Area 400m2/g)
GS-TC307 nano-Graphite Powder (Nominal BET Surface Area 350m2/g)
GS-4827 nano-Graphite Powder (Nominal BET Surface Area 250m2/g)
Applications for these powders include but not limited to: specialty coatings, specialty lubricants,
source of graphene materials, electrically conductive coating, thermally conductive coating and matrix additive,
IR absorbing materials, EMF/EMP shielding applications, radar shielding, polymer reinforcement, graphite oxide precursor,
graphitic/amorphous carbon hybrid materials , reactive carbon material for carbide synthesis, reactive carbon material
for special-case metallurgical reduction reactions, carbon particle surface energy studies, fine particle agglomeration studies,
novel carbon surface functionality investigations, capacitor substrate, ultra-fine substrate for catalyst support,
formation of ultra-fine voids in dense ceramic materials and components, pressure and/or shock damping,
novel heat transfer materials, novel functional pigments, phase-change heat exchanger heat transfer compounds,
dispersed phase RF/EMR attenuation, high impedance brushes, non-organic filler for grease thickening to replace or
enhance conventional soaps, friction and wear components.
Friday, July 22, 2011 -- GraphiteStore.com has expanded its selection of graphite lubricants by adding
the SLIP Plate®
line of Premium Dry-Film Graphite Products. The benefits of using SLIP Plate® products on equipment and tool surfaces include
wear resistance, increased flow characteristics, corrosion resistance and sticking reduction. Several premier equipment OEMs
endorse SLIP Plate® for their equipment. Our new products include:
Slip Plate® #1
which contains the highest concentration of friction fighting graphite, and produces a durable coating with greater lubricity,
and better bonding strength, than any other graphite coating on the market. We offer this in both can and aerosol form to accommodate
various application methods.
Slip Plate® #4
is a water-based, environmentally friendly alternative to petroleum-based dry film graphite coatings. It has been formulated
using a proprietary binder and particle suspension system with a natural graphite powder, producing an excellent abrasive
and corrosion resistant coating.
Slip Plate® Oven Chain Lubricants
are designed around unique, natural graphite that offers superior lubricity under extreme conditions.
Hot Oven Chain Lubricant
is a water-based mixture that effectively carries graphite to chain pins and bushings, while
Cold Oven Chain Lubricant
uses a light oil based suspension to effectively carry graphite. The unique binder system utilized by these two products creates
a very durable coating while the particle distribution allows graphite particles to penetrate very tight spaces. Use these to prolong
the life of your chain and reduce noise.
For easy, do-it-yourself lubrication jobs,
SLIP Plate® products are
easy-to-use, dry-film lubricants that eliminate almost any sliding friction problem as well as environmental barrier on farming,
industrial, and home equipment.
Friday, March 26, 2010 -- In response to a growing demand from our customers for carbon-fiber related products,
we are proud to announce two new additions to our carbon-fiber store:
Twill 2x2 weave
carbon fiber fabrics.
Plain is the most commonly used type for lightweight aerodynamic parts, while 2x2 twill weave fabric offers the cosmetic appearance
so desirable on modern composite parts. These fabrics are manufactured with the highest quality medium modulus (34 Msi) carbon fiber and
exhibit higher specific stiffness-to-weight ratios than any other comparable reinforcement materials.
Monday, May 27, 2009 -- In an on going process to expand our inventory of high
temperature insulation and gasketing products GraphiteStore.com introduced four new product types:
PAN Carbon Felt
PAN Graphite Felt
Rayon Carbon Felt
Rayon Graphite Felt
Carbon and graphite felts are designed for use as high temperature insulation in resistance or
induction heated vacuum furnaces and invert gas furnaces. Made of carbon or graphite fibers, these
materials have low thermal conductivity and vapor pressure. They are used in oxidizing atmospheres
up to 350°C (662°F) and in protective atmosphere or vacuum up to 3000°C (5432°F).
Monday, October 13, 2008 -- In response to our customers' demand GraphiteStore.com added new line
of highly effective machinable
glass ceramic products. Manufactured by Corning Incorporated, these
offer continuous use temperature of 800°C and a peak temperature of 1000°C. Some major
products include coefficient of thermal expansion that readily matches most metals
and sealing glasses; non-wetting by most metals and plastics; near zero porosity, and unlike ductile materials,
they won't deform. These products are excellent insulators at high voltages, various frequencies, and high temperatures.
They can be machined to .0005"; surface finished to less than 20µin and polished to a smoothness of 0.5µin.-AA.
Monday, February 18, 2008 -- GraphiteStore.com introduces new category
Fuel cell components
comprised of two product types:
Standard Graphite Plates and
Composite Bipolar Plates.
These plates exhibit sufficient rigidity, while supporting membrane in the pressurized fuel cell environment,
preventing gas and liquid leaks; maintain structural integrity at high operating temperatures; offer excellent
corrosion resistance over long periods of time (years); provide good thermal and electrical conductivity.
Wednesday, November 14, 2007 -- GraphiteStore.com has significantly expanded its mechanical carbon
inventory by adding two new product types:
Blanks - molded carbon-graphite tubes (HT to 1200°F) and
Blanks - graphite plates for dry running vanes.
Introduction of these products allows us to service applications of up to 1,200°F, as well as manufacture
dry running vanes for vacuum pumps and compressors.
Friday, September 21, 2007 -- GraphiteStore.com is pleased to announce addition of Sialon tubes
to its family of ceramic products:
Sialon Tubes - Open Both Ends.
Superior to all other ceramic refractories, SIALON - alloy of silicon nitride and aluminum oxide, is extremely tough
and recommended for molten metal applications, high wear or high impact environments up to 1250°C. It is non-wetting
for most nonferrous metals, gas tight, chemically inert, resistant to corrosion and metal attack and features high strength,
hardness and thermal shock resistance.
Sialon thermocouples are used extensively for continuous temperature measurement in non-ferrous metals. In molten
aluminum and aluminum alloys, Sialon does not contaminate the melt, provides for continuous, reliable temperature
measurement and is resistant to degradation even in aggressive aluminum lithium alloys. Excellent corrosion
resistance of Sialon allows for the use of thinner walls, thereby providing faster response time and improved accuracy.
Sialon is a reliable and consistent vehicle for degassing non-ferrous molten metals. Resistance to thermal shock,
erosion and corrosion by chlorine at high temperatures provides extended service life and consistent gas diffusion.
Sialon low pressure stalk (LPS) tubes provide performance-cost advantages to aluminum die casters. They do not
require pretreatments or coatings; they won't contaminate the melt and will reduce downtime.
Monday, July 23, 2007 -- Reflecting on growing demand for Pyrolytic Graphite, GraphiteStore.com
is pleased to announce addition of two new product types:
Substrate Nucleated discs (PG-SN) and
Substrate Nucleated plates (PG-SN).
Pyrolytic Graphite is a unique form of graphite manufactured by decomposition of a hydrocarbon gas at very high temperature
in a vacuum furnace. The result is an ultra-pure product which is near theoretical density and extremely anisotropic. The
material is grown onto a substrate giving it a layered composition. This also means it has different properties in
different planes. In the C plane (across its layers) it has low thermal conductivity, acting as an insulator. In the A-B
plane (with the layers) it has very high thermal conductivity, acting as a superb conductor.
Pyrolytic Graphite offers high purity, impermeability and is stable to 3000°C. It is used to make sputtering
targets, ion beam grids, ion implant hardware, liquid phase epitaxy hardware, thermal insulators, rocket nozzles, etc.
Friday, March 30, 2007 -- GraphiteStore.com is pleased to announce addition of two new product types:
Purified graphite rods - fine extruded and
Purified graphite tubes - fine extruded.
These fine particle purified graphite products range in size from 3/4"DIA to 5.25"DIA and up to 146"L. They undergo
gas purification which brings total level of chemical impurities below 50 parts per million (ppm). Applications that
will benefit the most from purified rods and tubes are: laboratory boats, molds and crucibles; electrodes; anodes;
heat exchangers, heating elements, furnace parts, etc.
Thursday, June 1, 2006 --
GraphiteStore.com responds to market demand by adding hundreds of Tool Brushes to its
category. These brushes are organized by Application, Size, Tool Manufacturer and
Tool Type with references to OEM part numbers and model numbers allowing for easy and convenient
search and detailed technical presentation.
Monday, April 17, 2006 --
GraphiteStore.com expands its inventory of high temperature, corrosion resistant
with addition of Labware Crucibles
and Furnace Tubes.
Our Labware Crucibles category is represented by 99.8% Alumina and 89% Zirconia Crucibles, Boats, Trays, Boats,
Dishes and Discs. Our Furnace Tubes category is represented by 99.8% Alumina Tubes ranging from 0.5"DIA to 6"DIA
and up to 48" in length.
This newest addition of high quality labware crucibles and tubes allows us to offer most comprehensive
Technical Ceramics inventory in the industry.
Monday, August 22, 2005 --
GraphiteStore.com is proud to announce an addition of
Carbon Brushes to its online marketplace.
We are now able to offer hundreds of stock brushes for replacement and OEM markets for any given application:
Industrial, Fractional Horse Power (FHP), Slip Ring, Traction, Power Tool, Elevator, Fork Lift.
BUFFALO GROVE, IL and EDISON, NJ - Monday, April 18, 2005 --
GraphiteStore.com, a leading provider of
composite carbon, graphite and ceramic products, introduced today the new version of its online marketplace
enhanced by OpenRules rule engine.
The enhanced GraphiteStore.com operates 19 online stores that offer highly sophisticated, application specific
products and solutions for Aerospace, Automotive, Chemical, Petrochemical, Mining, Aluminum, Steel, Glass,
Semiconductor, and other industries.
With OpenRules open source software incorporated into GraphiteStore's online portal,
GraphiteStore's product managers are able to set and implement various rules guiding products' promotion
and placement across various categories and product types. Rules-based technology allows GraphiteStore's
marketing team to identify and direct customers to products of their interest. OpenRules engine supports
cross-selling and up-selling capabilities of GraphiteStore.com, creating a better user experience, while
improving time-to-market of GraphiteStore's products and services.
GraphiteStore.com is a specialized online marketplace servicing industry professionals in a multitude of
applications requiring strength, thermal conductivity, electrical resistance and friction properties of
carbon and graphite. GraphiteStore.com provides customers with a one-stop opportunity to find, learn,
compare and purchase online the widest selection of carbon, graphite, ceramic products and materials.
GraphiteStore.com headquarters are based in Buffalo Grove, Illinois, and can be found on the Web at
OpenRules, Inc. is a NJ-based corporation that
develops, supports and provides consulting services around Open Source Business Rule Engine commonly known
as OpenRules. For details, please visit
Monday, March 7, 2005 -- GraphiteStore.com deploys the new
Dryer bearings store which includes the following product types:
Dryer bearing inserts
Dryer bearing assemblies
Brief description: Dryer bearings and assemblies are used in gypsum board, ceiling tile, veneer, plywood, fiberboard,
panel and insulation board dryer applications. We supply complete hanger bearing assemblies with carbon graphite
full and half bearing inserts, as well as jacketed replacement cartridges for bracket assemblies in silver dot materials
as well as other materials.
Monday, September 27, 2004 -- GraphiteStore.com adds
Clay-Graphite Crucibles - A Shape (OLD)
product type to the Crucibles, molds, ingots store.
We offer high quality, economical clay graphite crucibles for non-ferrous metal melting applications. These crucibles are
essential components of any foundry's lifecycle, and can be ordered online and shipped the next day throughout the country
Thursday, May 6, 2004 -- GraphiteStore.com, Inc., a leading online provider
of composite carbon, graphite and ceramic products, and
OpenRules, Inc. announced today that OpenRules,
the first open source full-scale business rules framework, will enhance GraphiteStore's online marketplace.
OpenRules will support marketing promotions and improve cross-selling and up-selling capabilities of GraphiteStore.com,
creating a better user experience while improving time-to-market of GraphiteStore's products and services.
Looking for a solution that would make the manufacturing and retail processes more flexible and responsive
while leveraging its current IT infrastructure, GraphiteStore recognized earlier that its online operations will
require a Business Rule Engine. Such engine will allow the business logic that is embedded in business applications
to be represented as rules that can be managed by business users, improving product configuration and accelerating
investment in business process management. However, the analysis of the commercial business rules engines had shown
that the most of them do not fit GraphiteStore's requirements being unnecessary complicated, difficult to integrate
in the GraphiteStore's .Net environment, and prohibitively expensive. The analysis of the capabilities of the new
open source business rule engine OpenRulesT had shown that this product along with the services provided by OpenRules, Inc.
will deliver a practical, comprehensive while inexpensive solution for the GraphiteStore's needs.
With OpenRules in place, GraphiteStore will empower business managers to configure dynamic stores, in which
different combinations of products can be offered to customers based on their practical needs, shopping experience,
and in simple customized manner. "Using OpenRules, we will be able to easily and flexibly adjust and fine-tune our
product lines and processes without making changes in the system software," said Vladimir Novokhovsky, GraphiteStore's
general manager. "With OpenRules, we express our business rules in an intuitive format using just MS Excel familiar
to any business specialist. No learning of any new tools or languages is required. Therefore, rules can be easily
changed by business specialists without IT involvement. This enables GraphiteStore not only to be more efficient,
but also to be more responsive to the constantly changing and expanding product lines."
OpenRules, Inc. expects that after an initial OpenRules deployment as a part of GraphiteStore.com,
the product will also enable other manufacturers and retailers in global trade to configure, maintain and change
their business processes with increased agility in response to business growth and other dynamic business demands.
GraphiteStore.com is a specialized online marketplace servicing industry professionals in a multitude of applications
requiring strength, thermal conductivity, electrical resistance and friction properties of carbon and graphite.
GraphiteStore.com currently operates 17 stores that offer highly sophisticated, application specific products and
solutions for Aerospace, Automotive, Chemical, Petrochemical, Mining, Aluminum, Steel, Glass, Semiconductor, etc.
industries. GraphiteStore.com, Inc. headquarters are based in Buffalo Grove, Illinois, and can be found on the Web
OpenRules, Inc. is a NJ-based corporation whose specialists
are known to many leading US businesses as experts in developing practical decision support applications using
business rules, optimization, and workflow technologies. OpenRules, Inc. is the company that develops, supports and
markets the OpenRules product and provides related consulting and training services. For more details, please visit
Friday, February 13, 2004 -- GraphiteStore.com adds a new product type to the
Rods and tubes store and two new product types to the
Unidirectional roll-wrapped tubes
Unidirectional laminates, zero° layup (.007 - .021 thick)
Unidirectional laminates, zero° layup (.030 - .045 thick)
Roll-wrapped tubes are used typically where thin walled, lightweight reinforcement is required to provide additional
stiffness and higher strength to weight ratio than is available in
Unidirectional pultruded tubes.
The laminates can add stiffness to almost any material (i.e. fiberglass, foam, and balsawood) and are used in a variety
of applications such as aircraft and rocket fuselages, surfboards, boat centerboards and guitar neck reinforcement.
Friday, January 16, 2004 -- GraphiteStore.com deploys the new
Rods and tubes store. This store currently includes the following product types:
Unidirectional pultruded rectangular bars
Unidirectional pultruded rods
Unidirectional pultruded square bars
Unidirectional pultruded tubes
Brief description: Carbon fiber rods and tubes are manufactured by pulling or wrapping carbon fibers and
epoxy resin to a desired diameter/cross section to form a densely reinforced carbon composite. They are
extremely stiff and light and have a very low coefficient of thermal expansion, making them ideal for use as
a reinforcement material in light weight constructions such as model cars, music instruments, trade show presentations, etc.
Tuesday, November 4, 2003 -- GraphiteStore.com deploys the new
EDM Graphite store. This store currently includes the following product types:
AC-12 Roughing and Finishing, BLANKS,
AC-15 Finishing, BLANKS,
AC-17 Semi-Precision, BLANKS,
AC-40 Precision, BLANKS,
AC-50 Wire Cut, BLANKS,
Brief description: Due to its unique properties, iso-molded graphite is the ideal material of choice for conventional
sinker EDM applications. Proper material grade selection is one key component of insuring the efficient use of this
modern machining technique. A wide range of materials have been developed over the past decade each designed for specific
applications. Materials differ in density, strength, hardness and machinability which can affect metal removal rates,
electrode wear, surface finishes and dimensional tolerances.
Thursday, September 18, 2003 -- GraphiteStore.com adds the new product type
Metallurgical and machinery greases to the
Powders and aerosols store.
The items included in the store are:
339-S Graphite Grease
HyHeet GP Graphite Grease
MPG General Purpose Grease
AEL 384 Graphite Grease
These greases provide excellent protection and lubrication under extreme pressures, and in temperatures up to 1000 F.
Friday, September 5, 2003 -- GraphiteStore.com adds seven new product types to the
Sealing tapes, ropes, etc. store:
Ceramic fiber braids - round
Ceramic fiber braids - square
Ceramic fiber cloth
Ceramic fiber ropes - twisted 3/ply
Ceramic fiber ropes - high density
Ceramic fiber sleeves
Ceramic fiber tapes
Brief description: Ceramic fiber twisted and braided ropes, cloth, tape and sleeve for industrial use in
temperatures up to 2300 F. Typical applications for these products include gasketing, packing and sealing in and
around high-temperature heating equipment. These products exhibit excellent resistance to thermal shock,
corrosive attack and breakdown due to mechanical vibration and stress.
Wednesday, August 19, 2003 -- GraphiteStore.com deploys the a
Insulation and gasketing store. This store currently includes two product types:
Insulation fiber boards and
Insulation fiber boards, foil on one side (FOS)
recommended for high temperature vacuum furnaces.