Tempering of PEEK, PPS-GF and PPA: What heat treatment really achieves in 3D printing
Short answer: Tempering is a controlled heat treatment after the printing process. For semi-crystalline high-performance polymers, it determines whether the component meets the values specified in the data sheet. The degree of crystallinity of PEEK increases from approximately 17% to over 30%, and according to studies, its tensile strength ranges between 12% and 64%. The hot bending temperature of PPA-CF25 increases from 97°C to 199°C, thus exceeding 100 Kelvin. The heat deflection temperature of PPS-GF20 increases from 125.8°C to 219.6°C under a load of 1.8 MPa. Without heat treatment, these three materials are not high-temperature materials; they are expensive thermoplastics. The disadvantages include longer processing times, higher energy consumption, an increased risk of warpage, and, in the case of PPA, a significant loss of impact strength.
Those who purchase a component made of PEEK , PPS-GF20 , or PPA-CF usually receive a datasheet with excellent specifications – but the final product often fails to meet these requirements. The cause is rarely the printer itself, but rather the crystallinity, which may not develop sufficiently when printing semi-crystalline high-performance plastics.
This article explains when the additional effort for heat treatment is worthwhile, which temperature profiles should be used, and when tempering does more harm than good.
What happens during tempering in the component
Semicrystalline thermoplastics exhibit two characteristic temperatures. At the glass transition point (Tg), the amorphous regions become mobile, while at the melting point (Tm), the crystalline order breaks down. Between these two points lies a region where crystals can form. For PEEK, Victrex specifies a Tg of 143 degrees Celsius (beginning) and 150 degrees Celsius (midpoint), and a Tm of 343 degrees Celsius.
In FFF and FGF processes, each strand cools down within a few seconds. This often happens too quickly for crystallization to occur. The result is a component that has solidified in a partially amorphous state. In a study published in the *International Journal of Advanced Manufacturing Technology* (2024), DSC measurements of untreated FFF-PEEK samples revealed a crystallinity level of 16.6 percent, whereas the filament used already exhibited a crystallinity level of 28.5 percent. The printer had therefore destroyed the order and not restored it.
Tempering solves this problem. It pursues three goals, which Victrex clearly distinguishes in its tempering instructions:
1. Increased crystallinity . Higher crystallinity means higher strength, increased stiffness, reduced water absorption, and better material durability.
2. Reduction of residual stresses . Both the printing process and the subsequent mechanical processing cause stresses in the component that impair its mechanical performance.
3. Ensuring dimensional accuracy during operation . An untempered component exposed to consistently high temperatures recrystallizes during operation. This leads to dimensional changes in the already assembled part. This aspect is often overlooked in inquiries.
A practical tip for evaluating offers: Filament data sheets often fail to specify the temperature at which measurements were taken. This is a crucial detail; in the case of PPA and PPS, it can make all the difference between two completely different materials, as the following illustrations demonstrate. If you find values for injection-molded parts in a data sheet, you should examine them very carefully, as they are generally not applicable to printed components.
PEEK and CF/GF-PEEK: the greatest leverage
PEEK is the material for which tempering is best documented and yields the greatest benefits.
The standard profile used
Victrex describes a four-step process for additively manufactured components:
Step | Specification |
Heating | equilibrium temperature to at least 200 degrees Celsius |
Hold | 1 hour per millimeter of wall thickness |
Cool | 10 Kelvin per hour, until the system is below 140 degrees Celsius |
End | Turn off the oven and let it cool down to room temperature. |
The target temperature depends on the intended use. For simple stress relief, Victrex specifies temperatures of up to 230 degrees Celsius, and for maximum crystallinity, 300 degrees Celsius or more. Nowadays, the holding temperature should be at least 20 Kelvin above the maximum operating temperature of the component. Therefore, if a component is designed for continuous use at 180 degrees Celsius, it should not be released at 160 degrees Celsius.
The complete cycle time must be included in the calculation. With a wall thickness of 5 millimeters, a holding time of 5 hours, and a cooling ramp from 220 degrees Celsius to 140 degrees Celsius at a rate of 10 Kelvin per hour, the cycle time is approximately 13 to 15 hours. In the aforementioned study, measurements yielded more than 8 hours and 2.7 kilowatt-hours per sample. Therefore, tempering is an independent manufacturing step with its own cycle time and not a by-product.
What will measurably improve
Investigation | profile | Result |
Int. J. Adv. Manuf. Technol. 2024 | 200 degrees Celsius, 2 hours | Crystallinity increased from 16.6 to 32.1 percent, tensile strength increased from approximately 48 to 61 MPa, and Young's modulus increased from 3.5 to 4.4 GPa. |
Polymers 2022 (14, 5521) | 220 degrees Celsius, 72 hours, in a quartz sand bed | Tensile strength plus 37 to 64 percent, fracture toughness plus 33 to 45 percent |
Polymers 2026 (18, 1694) | 100, 150, 200 degrees Celsius, 1 hour each | Post-treatment temperature was the single strongest factor overall, accounting for 56 percent of the tensile strength, ahead of nozzle and bed temperature. |
Coatings 2022 (12, 827) | 250 degrees Celsius, 6 hours, CF and GF-PEEK | Interlaminar shear strength plus 16 percent, dimensional change and porosity less than 1 percent |
For purchasing departments, the results of the "Polymers 2026" study are crucial: Heat treatment has a greater impact on strength than any single printing parameter. A properly tempered component from a basic system can exhibit better properties than an untempered component from an expensive system.
Fiber-reinforced types behave differently.
CF-PEEK and GF-PEEK also benefit from this, but exhibit different property and risk profiles.
A study published in the journal "Coatings" (2022) determined that the optimal conditions for short-fiber-reinforced CF-PEEK and GF-PEEK were a temperature of 250 degrees Celsius for a duration of 6 hours. The improvements achieved through short-fiber reinforcement amounted to over 5 percent in tensile, flexural, and impact strength, and 16 percent in interlaminar shear strength – precisely the area in which printed components are most likely to fail.
Glass fiber reinforced variants prove to be significantly more resistant at high temperatures. A study published in the "Journal of Manufacturing and Materials Processing" (2026) compared unreinforced PEEK with PEEK-GF20. At 250 degrees Celsius, both materials showed improvements. However, at 300 °C, the unreinforced PEEK lost strength due to gas-induced porosity, while no such damage occurred in PEEK-GF20.
The borders that are rarely talked about
Brittleness. For unreinforced types, Victrex explicitly points out that while high tempering temperatures increase crystallinity, they significantly reduce elongation. A study published in the journal "Polymers" (2023) showed that after treatment at 300 °C for 2 hours, no yield zone was observed, only a purely brittle fracture. Therefore, maximum crystallinity is not a suitable optimization parameter for components that must withstand impact loads or stresses during assembly.
Surface oxidation. Victrex cites yellowing and surface oxidation as possible consequences of high annealing temperatures. This is particularly important for visible components.
Warping. Thin-walled or asymmetrical components tend to warp during free annealing. According to Victrex, it is common practice in additive manufacturing (AM) technology to use a sand-like material as a mechanical support. In the aforementioned study, a 72-hour annealing process in quartz sand was used to ensure more uniform heating.
However, there are also opposing views. Manufacturers of systems that print PEEK in its semi-crystalline state argue that this eliminates the need for subsequent heat treatment and the associated distortion. As an interim solution, hot air treatment during the printing process was investigated: This achieved a degree of crystallinity of 34.9% without additional time expenditure, although the mechanical properties were lower than those of furnace treatment (tensile strength 54 MPa compared to 61 MPa).
PPS-GF20: the tempering temperature determines the application range
The heat resistance of PPS is significantly lower than that of PEEK. PPS-GF20 has a glass transition temperature of 95 degrees Celsius and a melting point of 279.6 degrees Celsius. However, the crucial figure in the datasheet is the third: the crystallization temperature of 225.8 degrees Celsius. The tempering temperature of 130 degrees Celsius is almost 100 Kelvin lower than the temperature at which PPS actually crystallizes.
This is clearly evident from the values in our own data sheets. These values were determined using test specimens that were tempered for 10 hours at 130 degrees Celsius. If the emission occurs instead at 230 degrees Celsius, the thermal transition temperature changes dramatically.
Key figure | tempered at 130 degrees Celsius, 10 hours | tempered at 230 degrees Celsius | difference |
HDT according to ISO 75, 1.8 MPa | 125.8 degrees Celsius | 219.6 degrees Celsius | plus 93.8 Kelvin |
HDT according to ISO 75, 0.45 MPa | 236.3 degrees Celsius | 248.9 degrees Celsius | plus 12.6 Kelvin |
The jump to 1.8 MPa is the most important value for PPS users in this article. Under practical load, the operating temperature nearly doubles. A PPS-GF20 component tempered too low will deform under load at 130 degrees Celsius, while a component tempered at 230 degrees Celsius can withstand temperatures above 200 degrees Celsius. This is not a matter of fine-tuning, but rather a decision about whether PPS-GF20 is even suitable for the application.
It is also revealing that the values hardly differ at low loads (0.45 MPa): Anyone who relies on a nice figure of 0.45 MPa for their design will not notice the difference and will later be surprised by the distortions of the component.
The fact that PPS solidifies practically amorphously without controlled temperature is also well documented in the literature. A study in "Polymers" (2023), focusing on highly glass-fiber-reinforced PPS, found no crystalline peak in the X-ray diffraction pattern at a quenching temperature of 80 °C. Between 80 and 160 °C, the crystallinity index doubled, the tensile strength increased by 10%, the modulus of elasticity by 24%, the flexural strength by 17%, and the absorbed impact energy by 37%.
The most compelling evidence for post-printing heat treatment is the work of Kishore et al. (Additive Manufacturing, 2020) on short lengths of carbon fiber-reinforced PPS from large-format printing. Isothermal annealing at 250 °C for 18 hours improved the storage modulus above Tg for all tested types. This is crucial for PPS: without crystallinity, stiffness drops significantly above approximately 95 degrees Celsius, rendering half of the material's application ranges unusable.
The PPS-specific pitfall: The same study shows thermo-oxidative structural changes on the surface. Very long holding times just above the crystallization temperature (Tg) are no longer considered annealing, but rather aging. A 180-hour aging study of PPS-GF20 at 85–145 degrees Celsius showed a decrease in tensile strength from 130 to 70 MPa and a decrease in elongation at break from 7 to 3 percent, which was attributed to damage to the fiber-matrix interface and chain breakage. Discoloration and loss of gloss correlate measurably with the loss of properties. Therefore, discoloration in PPS is a sign of damage and not merely a cosmetic problem. In practice, this means short, hot annealing in the crystallization temperature range, not long, lukewarm annealing just above Tg.
Regarding the availability of information: For PPS, there is no publicly published emissions profile with heating and cooling rates, unlike the one Victrex provides for PEEK. The defined endpoints are clear; the path to them is taken from the PEEK methodology and verified by the component.
PPA-CF25 and PPA-GF15: without tempering, they are not high-temperature materials.
The effect is greatest with PPA and is illustrated in our own datasheet. Untreated PPA-CF25 is not a high-temperature material. Its temperature regulation temperature is 97 degrees Celsius, which is comparable to that of a well-processed technical polyamide. In the tempered state, it is 199 degrees Celsius.
Key figure | PPA-CF25 untempered | PPA-CF25 tempered | PPA-GF15 untempered | PPA-GF15 tempered |
HDT 0.45 MPa (Method B) | 97 degrees Celsius | 199 degrees Celsius | 84 degrees Celsius | 185 degrees Celsius |
HDT 1.8 MPa (Method A) | 84 degrees Celsius | 126 degrees Celsius | 80 degrees Celsius | 112.2 degrees Celsius |
Charpy XY, unnotched | 13.1 kJ/m² | 7.3 kJ/m² | 12.2 kJ/m² | 7.1 kJ/m² |
The heat deflection temperature increases by approximately 100 Kelvin under low stress and by more than 40 Kelvin under high stress. The reason is the same as for PEEK and PPS: PPA has a glass transition temperature of only 80 degrees Celsius and a melting point of 239 degrees Celsius (PPA-CF25) or 232 degrees Celsius (PPA-GF15). Between these points lies a wide window in which the pressure-hardened, amorphous material recrystallizes. Without this step, the order is lost, and consequently, so is the thermal deformation temperature.
The price is listed in the same table. Tempering reduces the Charpy impact strength by over 40 percent, from 13.1 to 7.3 kJ/m² for PPA-CF25 and from 12.2 to 7.1 kJ/m² for PPA-GF15. This is the same mechanism as with embrittlement in PEEK: increased crystallinity, less energy absorption in the crack. For a housing subjected to hot and static loads, replacement is clearly the right choice. If you want a component designed to absorb shocks, you need to make an informed decision.
One more note on interpretation: The XY properties in our PPA datasheet are determined using an annealed sample, while the Z properties are determined using an unannealed sample. Calculating the anisotropy from both columns means working with two different material states.
Drying is not tempering
These two steps are often confused when working with PPA, even though they serve different purposes and take place in different parts:
Drying involves the filament and takes place before printing. Its purpose is to remove water from the material to prevent hydrolysis, bubbles, and poor layer adhesion in the nozzle .
Annealing affects the printed component and takes place after printing. Its purpose is to increase crystallinity and reduce internal stresses.
Both are essential for PPA and neither replaces the other. Moisture absorption is significantly higher for PPA than for other materials in this range: 1.09 percent for PPA-CF25 and 1.37 percent for PPA-GF15 according to ISO 62, compared to 0.11 percent at equilibrium for PPS-GF20 and 0.03 percent for unreinforced PEEK.
A study published in the journal "Applied Sciences" (2026) measured the drying time of PPA-CF. Time to 0.6 percent residual moisture:
Drying temperature | Time until 0.6 percent residual moisture |
70 degrees Celsius | approximately 67 hours |
95 degrees Celsius | approximately 6 hours |
120 degrees Celsius | approximately 1.3 hours |
The 50-fold difference between 70 and 120 degrees Celsius is the strongest argument against the common practice of producing PPA in a standard filament dryer at 70 degrees Celsius. 3DXTech's manufacturer recommendation for PPA and HTN is 120 degrees Celsius for 4 hours.
Be careful with the nomenclature: The designations PPA, HTN, PA6T, and PA10T refer to copolyamides that differ significantly in some respects. Our PPA-CF25 melts at 239 degrees Celsius, while other types marketed as PPA melt between 285 and 315 degrees Celsius, according to technical literature. Mixing the properties of different products leads to misinterpretations, including regarding the temperature profile. Always request the product data sheet for the specific type you are using.
Three questions for every datasheet
The figures above illustrate why the characteristic value is of little significance without considering the temperature state. PPA-CF25 has a heat deflection temperature of 97 or 199 degrees Celsius depending on the temperature state, while PPS-GF20 exhibits a temperature of 125.8 or 219.6 degrees Celsius at a load of 1.8 MPa. It is the same material, the same component, the same geometry.
Therefore, check the following information in every offer and every data sheet:
In what release state was the measurement performed? Uncoated, lightly coated, or at crystallization temperature? If this information is missing, the value is not suitable for design purposes.
At what load does the heat deflection temperature apply? 0.45 MPa or 1.8 MPa? For PPS-GF20, these two values differ by more than 110 Kelvin and are affected very differently by the release.
Does this value apply to a printed or injection-molded component? Injection-molded values cannot be transferred, even partially, to printed components.
Therefore, our material data sheets specify the temperature status for each changed characteristic value, including values that deteriorate due to emission.
Material comparison at a glance
PEEK / CF-PEEK / GF-PEEK | PPS-GF20 | PPA-CF25 / PPA-GF15 | |
Glass transition Tg | 143 degrees Celsius | 95 degrees Celsius | 80 degrees Celsius |
Melting point Tm | 343 degrees Celsius | 279.6 degrees Celsius | 239 or 232 degrees Celsius |
Crystallization temperature | 200 to 300 degrees Celsius in the window | 225.8 degrees Celsius | between Tg and Tm |
Sensible temperature level | 200 to 250 degrees Celsius, for maximum crystallinity up to 300 degrees Celsius | Approximately 230 degrees Celsius, significantly more effective than 130 degrees Celsius | According to the manufacturer's instructions for the compound, the effect is shown in the data sheet. |
Proven benefits | Crystallinity increased from 17 to over 30 percent, tensile strength increased by 12 to 64 percent. | HDT at 1.8 MPa increased from 125.8 to 219.6 degrees Celsius | HDT at 0.45 MPa from 97 to 199 degrees Celsius (CF25) |
Price of tempering | Loss of ductility, oxidation risk | Oxidative damage due to incorrect profiling; discoloration as a warning signal | Impact resistance reduced by over 40 percent |
Additionally, please note | Delay, processing time 8 to 15 hours | short and hot instead of long and lukewarm | Dry the filament at 120 degrees Celsius before printing. |
Maximum component size at Malping | 510 x 510 x 410 mm (FGF) | up to 300 mm (FFF) | 350 x 350 x 450 mm (FFF) |
When to temper and when not to temper
With PPS-GF20 and PPA, the question is usually already answered: Without tempering, these materials do not offer the heat resistance for which they were selected. Using PPA-CF25 without tempering means buying a material rated for 199 degrees Celsius, but only achieving 97 degrees Celsius. With PEEK, the situation is more open, as even a PEEK component made without tempering is often still a very good component.
Tempering is worthwhile if at least one of the following points applies:
The material is PPS-GF20 or PPA, and the component is designed for operation at high temperatures. This is the clearest example, as can be seen in the images above.
The component operates continuously at temperatures above 100 degrees Celsius, or in the case of PEEK, at temperatures above 140 degrees Celsius. Otherwise, it recrystallizes during operation and changes its dimensions.
It comes into contact with media, cleaning chemicals, or hot steam. Higher crystallinity reduces absorption and corrosion.
It is subject to continuous stress and does not creep. Creep strengths in data sheets are usually determined using hardened samples, typically PEEK that has been cured for 2 hours at 200 degrees Celsius.
It is processed and must retain its dimensions afterwards.
Stiffness and strength are crucial for the design, and the data sheet was provided in printed form.
Do not temper if:
the component is a room temperature device, a prototype, or an assembly device.
Toughness and impact resistance are more important than stiffness and heat resistance. When tempering PPA, the impact strength decreases by more than 40 percent; this is a real compromise, not just a formality.
the geometry is thin-walled, large-area and asymmetrical, and the risk of deformation outweighs the benefit,
The delivery time is crucial and none of the above points apply.
It is important that this decision is made consciously and taken into account in the offer. The untempered PPA component is not wrong; it is simply a different component.
The order in the process is crucial.
A crucial detail that determines the dimensional accuracy of the finished part: first tempering, then machining.
Annealing alters the dimensions. Even under optimal conditions, the dimensional change can be up to 1 percent, as studies with CF and GF-PEEK coatings at 250 degrees Celsius for 6 hours have shown. Machining a fitting or thread before annealing is essentially machining it twice.
The machining process itself creates stresses within the component. For highly stressed parts, a second, milder annealing cycle after machining can therefore be particularly beneficial to relieve stresses and prevent crystallinity. Victrex specifically mentions this scenario as an application of tempering.
The malping process proceeds as follows:
Drying of the filament or granules, followed by printing using the FFF or FGF process.
Tempering according to material- and wall thickness-specific profile, with mechanical support for critical geometries.
Machining of functional surfaces and threads by our qualified CNC partner (threads from M8).
Dimensional control, possibly with optical digitization using our 3D scanner.
Optional second stress reduction cycle.
General tolerances: FFF ±0.2 mm, FGF ±0.2–0.5 mm, CNC-machined ±0.05 mm. FFF production volume: max. 350 x 350 x 450 mm. FGF production volume: 510 x 510 x 410 mm.
What this means for your request
You don't need to specify a temperature profile. It would be helpful if you could tell us three things:
Continuous fluctuations in operating temperature and component temperature
Media contact, cleaning methods and sterilization
Critical dimensions with tolerances so that we can determine what is produced before and after tempering.
We process PEEK, CF-PEEK, and GF-PEEK in technical and medical grades, as well as PPS-GF20, PPA-CF25, and PPA-GF15. The standard lead time is two weeks and includes tempering. Our material data sheets specify the tempering status for each material, even if tempering would reduce its value.
Request a component or go directly to PEEK manufacturing according to drawing .
Frequently asked questions about tempering high-performance polymers
What is tempering in 3D printing?
Tempering is a controlled heat treatment performed after printing. The component is heated in a furnace to a temperature between the glass transition point and the melting point, held at this temperature, and then slowly cooled. The aim is to increase crystallinity and eliminate internal stresses.
At what temperature is PEEK tempered?
Victrex specifies temperatures up to 230 degrees Celsius for stress relief and 300 degrees Celsius and higher for high crystallinity. In practice, temperatures of 200–250 degrees Celsius are common. The holding time is approximately one hour per millimeter of wall thickness, and cooling occurs at a rate of about 10 Kelvin per hour to below 140 degrees Celsius.
How much strength does tempered PEEK gain?
The published values range from plus 12 to plus 64 percent tensile strength, depending on profile, fill level, and web orientation. The degree of crystallinity typically increases from around 17 to over 30 percent.
Can tempering damage a component?
Yes, and measurably so. The Charpy impact strength of PPA decreases by more than 40 percent due to emissions, from 13.1 kJ/m² to 7.3 kJ/m² in the case of PPA-CF25. Excessively high temperatures embrittle unreinforced PEEK, leading to pure brittle fracture and potentially surface oxidation; gas-induced porosity has been observed in unreinforced PEEK at 300 degrees Celsius. For PPS, prolonged holding times just above the glass transition temperature tend to lead to aging rather than improvement. Emission is therefore always a compromise: heat resistance and stiffness versus toughness.
Does a component warp during tempering?
The risk is particularly high with thin-walled, large-area, or asymmetrical parts. In additive manufacturing, it is common practice to mechanically support components in a sandy medium during annealing. The dimensional change itself is less than one percent under good conditions, but it must be taken into account in the manufacturing process.
Do PPS-GF20 components need to be tempered?
Yes, if the component is intended for operation at high temperatures and under load. A crucial factor is the annealing temperature: After 10 hours at 130 degrees Celsius, the thermal resistance under a load of 1.8 MPa is 125.8 degrees Celsius, while annealing at 230 degrees Celsius results in a temperature of 219.6 degrees Celsius. That's a difference of almost 94 Kelvin for an identical component. The reason: The crystallization temperature of PPS-GF20 is 225.8 degrees Celsius, so annealing at 130 degrees Celsius is significantly below the material's actual crystallization temperature.
Does PPA need to be tempered?
Yes. Uncured PPA is not a high-temperature material. The heat deflection temperature at 0.45 MPa increases with tempering from 97 °C to 199 °C for PPA-CF25 and from 84 °C to 185 °C for PPA-GF15, which corresponds to approximately 100 Kelvin. At 1.8 MPa, the increase is from 84 °C to 126 °C and from 80 °C to 112.2 °C, respectively. Using uncured PPA means paying for a high-temperature material but achieving the heat deflection temperature of an engineering polyamide. However, tempering also results in a loss of impact strength of over 40%.
Is drying the same as tempering?
No, these are two separate steps with different purposes. The filament is dried before printing to prevent hydrolysis and bubbles in the nozzle. The finished part is annealed after printing to increase crystallinity and eliminate internal stresses.
How can I tell if a datasheet value is considered tempered?
It is essential to ensure that the value is clearly specified. If this information is missing, the value is uninterpretable, as the heat deflection temperatures of PPA and PPS can differ by up to 100 Kelvin between the annealed and unannealed states. Furthermore, it is crucial to note the stress at which the heat deflection temperature is applied (0.45 or 1.8 MPa) and whether the value is determined using a printed or injection-molded sample.
Tempering before or after machining?
Generally, tempering should be performed first, followed by machining of fits, functional surfaces, and threads, as tempering alters the dimensions. For highly stressed components, a second, milder cycle after machining may be beneficial to relieve the accumulated stresses.
Sources
Malping material data sheets PEEK, PPS-GF20 and PPA-CF25/PPA-GF15 (printed test specimens, as of 2026)
Victrex, Additive Manufacturing Annealing Guidelines, V.3, November 2021:victrex.com
Victrex, PEEK finishing operations guide, January 2022:victrex.com
Victrex PEEK 450G datasheet:victrex.com
Int. J. Adv. Manuf. Technol. 2024: link.springer.com
Polymers 2022, 14, 5521:mdpi.com
Polymers 2026, 18, 1694:mdpi.com
Polymers 2023, 15, 2209:mdpi.com
Coatings 2022, 12, 827:mdpi.com
JMMP 2026, 10, 110:mdpi.com
Kishore et al., Additive Manufacturing 2020: doi.org
Polymers 2023, 15, 3179:mdpi.com
Polymers 2022, 14, 1275:mdpi.com
Applied Sciences 2026, 16, 5056:mdpi.com
Ensinger, PPS material information: ensingerplastics.com
3DXTech, Filament Drying Instructions:3dxtech.com
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