Ceramic slurries for additive manufacturing of technical ceramics by injection molding

The usage of traditional ceramic injection molding CIM slurries with 3D printed durable and/or water soluble sacrificial molds has unique benefits in comparison to direct printing of ceramic slurries based on photopolymer resins, to say:

full range of technical ceramics and metals slurries can be cast using traditional CIM and MIM feedstocks
higher sintering density, lower microporosity vs metal Selective Laser Sintering SLS and direct printing of ceramics and metals by SLA and jetting
less productive limitations, much faster and ecological debinding without solvents, with water for faster debinding and sintering times without limitation of thickness vs. ceramic and metal printing by SLA and jetting
increased isotropy vs metal Selective Laser Sintering SLS and direct printing of ceramics and metals by SLA and jetting
lower costs since our soluble 3D resins allow the printing of sacrificial or durable molds with affordable SLA, DLP and LCD printers with prices ranging from 300 to 10,000 Euros and with traditional injection molding machines and traditional ceramic and metal feedstocks

Traditional Ceramic Slurries with these features and benefits can be injected in 3D printed molds made with our durable and/or water soluble sacrifical 3D resins:

excellent dispersion and injection flow of high micron and submicron ceramics with additions up to 65% volumen concentrations
very high resolution after injection in durable or water based sacrificial injection molds
high quality
controlled and reproducible process shrinkage
minimum expansion coefficient and wide temperature interval of debinding to prevent micro-fractures
very high resolution of 20 microns of final products
controlled shrinkage

Typical properties of Sintered Ceramics

Material	Density (g/cm3)	Flexural Strength (MPa)	Fracture Toughness (MPa√m)	Vickers Hardness (HV) GPa	Melting Temperature ºC	Sintering Temperature ºC	Properties and Benefits
Alumina Al2O3	3.8-3.9	350-600	4-6	15-20	2000	1100-1300 air	Excellent thermal stability, wear resistance, low electrical conductivity (electrical insulator), high chemical and corrosión resistance, good mechanical strength up to 1000ºC, high expansion coefficient, thermal shock resistance
Zirconia ZrO2	5.8-6	400-900	6-7	10-15	2700	1450-1500 air	High strength, fracture toughness, hardness, wear resistance, good frictional behaviour, non-magnetic, electrical insulation, low thermal conductivity, corrosion resistance in acids and alkalis, modulus of elasticity similar to steel, coefficient of thermal expansion similar to iron
Yttria stabilized zirconia (YSZ/Y-TZP)	-	900-1200	9-10	12-13	2400-2700	1450-1500 air	Outstanding hardness, strength and fracture toughness, excellent chemical and wear resistance Used in many high wear applications: dental, engineering, microreactors, equipment,
Silicon carbide SiC/SiSiC	3.1-3.2	350-800	4-5-5	18-22	2700 decomposes	1200-1450, up to 2200°C, Ar, N₂ or similar inert atmosphere	Outstanding thermal shock resistance, extreme hardness, high thermal conductivity, low expansion coefficient, semiconductor, high oxidation resistance, refractive index greater than a diamond. Typical operating temperatures 1000-1500ºC
Silicon niride Si3N4	3.1-3.3	700-900	6-7	13-20	1900 decomposes	1100-1450, up to 1700, air	High strength, low electrical and thermal conductivity (electrical insulator), high resistance to molten metals, excellent thermal shock resistance, high wear resistance Used in many dielectric heating or RF (radio frequency) heating applications where the material is in contact with hot metal parts and in automotive and machine tool industries for bearing and wear parts which run in abrasive environments.
Hydroxy apatite HA	2.5-2,6	21	1-2	5	800-1200 decomposes	1200-1250, air	Chemically similar to the mineral component of bones and hard tissues in mammals, classed as bioactive and biocompatible, supports bone ingrowth and osseointegration when used in prosthetics, orthopaedic, dental and maxillofacial applications

Material	Properties and Benefits	Main Applications
Alumina Al2O3	High hardness and mechanical strength under compressive loading, excellent thermal stability, wear resistance, low electrical conductivity ( high frequency electrical insulator), high temperature, chemical and corrosion resistance, good mechanical strength up to 1000ºC, high expansion coefficient, thermal shock resistance, excellent wear resistance, good anti-plasma	Excellent electric insulator products, sand and shot blasting nozzles, welding shield and nozzles for laser cutting guns, tubes with single hole to multi core/hole cavities, seals, textile wear parts and thread guides, piston and sleeves for chemical pumps, corrosion resistance components, ceramic coldplate for power electronic cooling, heating element fixtures, surgical instruments
Zirconia ZrO2	High hardness, mechanical strength and toughness, fracture toughness, hardness, wear resistance, good frictional behaviour, non-magnetic, electrical insulation, low thermal conductivity, , modulus of elasticity similar to steel, coefficient of thermal expansion similar to iron, excellent wear resistance, high fracture toughness, low thermal conductivity, good chemical and corrosion resistance in acids and alkalis	Pump parts, dies, knives, cutting blades, spikes, scissors, wear parts for wear applications, valves and pump components,ceramic plain, balls and roller bearings, tubes, fixtures for high temperature applications, copper tube extruding & reducer diez, thermal insulation components, wear resistance and cutting blades, Dental restorations and appliances, fuel cell components, structural ceramics
Yttria stabilized zirconia YSZ/Y-TZP	Outstanding hardness, strength and fracture toughness, excellent chemical and wear resistance	Used in many high wear applications, dental restorations: crowns, copings and bridges, engineering, microreactors, analyitic equipment
Silicon carbide SiC/SiSiC	High hardness, good room and high temperature and strength, outstanding thermal shock resistance, extreme hardness, high thermal and electrical conductivity, low expansion coefficient, semiconductor,high oxidation resistance, refractive index greater than a diamond, operating temperatures 1100-1500ºC, high temperature strength, high chemical and corrosión resistance, high fracture toughness,	High temperature resistant parts, mechanical seals, sliding bearings, mechanical seals for chemical pumps, wear parts such as thread guides, Kiln furniture crucibles, burners for high temperature furnaces, sand blasting nozzles, heat exchangers tubes, emiconductor parts, wafer processing plates & discs components
Silicon nitride Si3N4	High strength, low electrical and thermal conductivity (electrical insulator), high resistance to molten metals, excellent thermal shock resistance, high wear resistance, high temperature strength, excellent thermal shock resistance, wear resistance, light weight (low density), chemical resistance, good fracture toughness, mechanical fatigue, excellent compressive strength and creep resistance, excellent non-wetting property with good oxidation resistance	Dielectric heating or RF (radio frequency) heating applications in tool industries for bearing and wear parts engines in abrasive environments, antiwear liner, powder equipment, molten metal parts, metal forming tools. Gas turbine engines, turbocharger rotors, high temperature propulsión components, foundary components. Automotive: bearings, tappet shims and buckets, cam rollers, high pressured pumps parts, turbocharge rotors, rocker arm tips, welding location pins, squeeze rollers for radiator tube manufacturing. Balls & bearings.Non-ferrous foundries: thermocouples sheaths, riser tubes, heater tubes, valve rods, valve seats, aluminium powder atomizer tubes, molten metal pumps parts, rotor for degassing shaft, launders due to its high temperature capacity, excellent thermal shock, non-wetting properties. Coordinate Measuring Machine Styluses CMM: various types of styluses, styluses rods, plain bearings, ceramic balls
Hydroxy apatite HA	Chemically similar to the mineral component of bones and hard tissues in mammals, classed as bioactive, supports bone ingrowth and osseointegration	Used in prosthetics, orthopaedic, dental and maxillofacial applications

Typical Properties of highly pure Technical Ceramics	Alumina	Zirconia	SiC/SiSiC	Si3N4
Bulk Density g/cm3	3.8-3.9	5.8-6	3,1-3.2	3.1-3.3
Melting temperature ºC	2000	2715	2730 decomposes	1900 decomposes
Maximum operating temperature ºC	1500-1650	900-1000	1100-1500	1000-1150
Vickers Hardness HV (GPa)	15-20	10-15	18-22	13-20
Flexural Strength MPa	350-600	400-900	350-800	700-900
Compressive Strength MPa	2000-2600	2000-2500	1700-2400	700-2700
Young's Modulus of Elasticity GPa	360-380	200-220	430-440	270-300
Poisson's Ratio	0.23	0.31	0.16	0.28
Fracture Toughness MPa√m	4-6	6-7	4.5-5	6-7
Coefﬁcient of Linear Thermal Expansion 40～400℃ /40～800℃ (×10-6/℃)	7.2/8	10/11	3.7/4.4	2.8/3.3
Thermal Conductivity　 20℃ W/(m・K)	30-34	2.9-3.1	60-200	23-54
Speciﬁc Heat J/(g・K)	0.78-0.79	0.46-0.47	0.67	0.65-0.66
Heat Shock Resistance (in water) ℃	200-250	300-400	380-420	800-900
Dielectric Strength KV/mm	12-15	11-13	-	12-13
Volume Resistivity 20℃ Ω・cm	>10¹⁴	>10¹⁴	10⁵-10⁸	>10¹⁴
Volume Resistivity 300℃ Ω・cm	10¹³	10⁸	10⁴	10¹²
Volume Resistivity 500℃ Ω・cm	10¹⁰	10⁴	10³	10¹⁰
Dielectric Constant 1MHz	9.7-9.9	28-32	-	8.3-9.6
Dielectric Loss Angle 1MH (×10-4)	1-2	16-17	-	5-19
Loss Factor ×10-4	10-20	470-520	-
Nitric Acid（60％）90℃,24H	10	0	<0.04	0.2-1.1
Sulphuric Acid（95％）95℃,24H	<0.2	<0.05	0	0
Caustic Soda（30％）80℃,24H	<0.05	<0.1	0	0.1-0.5

Please contact us to consult about our customised Ceramic slurries and your specific performance goals at: info@3Dresyns.com