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CAB vs CTA

Polymer · grade comparison

CAB and CTA are both polymer grades. CTA is the stronger of the two: yield strength 55 MPa (7.98 ksi) against 28 MPa (4.06 ksi) for CAB, about 96% more; tensile strength follows at 70 MPa (10.2 ksi) vs 32 MPa (4.64 ksi). In exchange, CAB is the more ductile: elongation 60% versus 25% for CTA. CAB is lighter (1.19 g/cm³ vs 1.3 g/cm³ for CTA) and CTA is stiffer (3.2 GPa vs 1.4 GPa). On the shop floor, CAB machines more easily (very good vs good).

CABChoose it when the part is bent, formed or impact-loaded, or when weight is the constraint.

CTAChoose it when strength drives the design, or when the part sees heat.

CAB vs CTA: properties

CABCTA

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

1.4 GPa0.2 Msi
3.2 GPa0.46 Msi

Shear Modulus

0.5 GPa0.07 Msi
1.2 GPa0.17 Msi

Bulk Modulus

2 GPa0.32 Msi
—

Tensile Strength (Ultimate)

32 MPa4.6 ksi
70 MPa10.2 ksi

Yield Strength (0.2% offset)

28 MPa4.1 ksi
55 MPa8 ksi

Elongation at Break

60%
25%

Compressive Strength

45 MPa6.5 ksi
105 MPa15.2 ksi

Compressive Modulus

1.3 GPa0.19 Msi
—

Flexural Strength

45 MPa6.5 ksi
85 MPa12.3 ksi

Flexural Modulus

1.3 GPa0.19 Msi
2.9 GPa0.42 Msi

Shear Strength

30 MPa4.4 ksi
50 MPa7.3 ksi

Fracture Toughness (K_IC)

2 MPa·√m1.8 ksi·√in
—

Izod Impact, Notched

200 J/m3.7 ft·lbf/in
60 J/m1.1 ft·lbf/in

Hardness, Shore D

75 Shore D
—

Hardness, Rockwell R

95 HRR
115 HRR

Hardness, Rockwell M

—
65 HRM

Same in both: Poisson's Ratio 0.38

Physical

Density and transition temperatures.

Density

1.19 g/cm³0.04 lb/in³
1.3 g/cm³0.05 lb/in³

Glass Transition (Tg)

115°C239 °F
185°C365 °F

Water Absorption (24 h)

1.3%
2.5%

Water Absorption (Saturation)

2.6%
6%

Light Transmission

89%
92%

Melting Temperature (Tm)

—
300°C572 °F

Same in both: Refractive Index 1.475

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

0.2 W/m·K0.12 BTU/hr·ft·°F
0.21 W/m·K0.12 BTU/hr·ft·°F

Specific Heat Capacity

1,600 J/kg·K0.38 BTU/lb·°F
1,500 J/kg·K0.36 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

130 µm/m·K72.2 µin/in·°F
80 µm/m·K44.4 µin/in·°F

Max Service Temperature (continuous)

70°C158 °F
95°C203 °F

Heat Deflection Temp. @ 0.45 MPa

75°C167 °F
120°C248 °F

Heat Deflection Temp. @ 1.8 MPa

58°C136 °F
95°C203 °F

Vicat Softening Point (B50)

100°C212 °F
140°C284 °F

Limiting Oxygen Index

20%
19%

Max Service Temperature (short-term)

95°C203 °F
140°C284 °F

Same in both: Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Dissipation Factor (1 MHz)

0.03
0.025

Surface Resistivity

1×10¹⁴ Ω
1×10¹³ Ω

Same in both: Electrical Resistivity 1×10¹² Ω·m3.94×10¹⁹ µΩ·in · Dielectric Strength 16 kV/mm406 V/mil · Dielectric Constant (1 MHz) 3.4 · Volume Resistivity 1×10¹⁴ Ω·cm · Comparative Tracking Index (CTI) 600 V

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

50 / 100
—

UV / Weathering Resistance

70 / 100
45 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

75 / 100
65 / 100

Formability (cold)

80 / 100
70 / 100

Polishability

85 / 100
80 / 100

Melt Flow Rate

10 g/10 min
—

Processing Melt Temperature (typ.)

200°C392 °F
245°C473 °F

Mold Temperature (typ.)

55°C131 °F
70°C158 °F

Same in both: Weldability 60 / 100 · Mold Shrinkage 0.5%

Sustainability

Primary-production footprint per kilogram.

Embodied Water

500 L/kg59.9 gal/lb
600 L/kg71.9 gal/lb

Typical Recycled Content

0%
2%

Same in both: Embodied Energy (primary production) 105 MJ/kg45,142 BTU/lb · Embodied Carbon (primary production) 4.5 kg CO₂/kg

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

27 kN·m/kg
54 kN·m/kg

Specific Stiffness (E / density)

1.2 MN·m/kg
2.5 MN·m/kg

Modulus of Resilience

280 kJ/m³
473 kJ/m³

Same in both: Thermal Diffusivity 0.1 mm²/s · Thermal Shock Resistance Index 0

Strength versus weight

Yield strength against density for every polymer grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

0.1110100123Density (g/cm³)Yield strength (MPa) — log scaleCTACAB

Manufacturing and finishing

CapabilityCABCTA
Default condition——
Relative cost$$$ Premium$$$ Premium
Min. machined wall——
Best machined surface——

CAB vs CTA — frequently asked

Is CTA stronger than CAB?

Yes. CTA has a typical yield strength of 55 MPa (7.98 ksi) against 28 MPa (4.06 ksi) for CAB — about 96% more. Tensile strength is 70 MPa (10.2 ksi) vs 32 MPa (4.64 ksi).

Which is cheaper, CAB or CTA?

Both sit in the same relative cost tier ($$$, premium); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which is easier to machine, CAB or CTA?

CAB. Its machinability rates very good (75/100) against good (65/100) for CTA.

Ready to make it?

Upload a CAD file and FabDigit prices the part in CAB and CTA side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.

Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.