FabDigitFabDigit

JGS1 vs Vycor 7913

Glass · grade comparison

JGS1 and Vycor 7913 are both glass grades. JGS1 is harder — 750 HV against 620 HV for Vycor 7913 — which matters for wear surfaces and threads. JGS1 is stiffer (72 GPa vs 67 GPa) and JGS1 runs hotter in service (1,050°C vs 900°C continuous).

JGS1Choose it when surface hardness matters, or when the part sees heat.

JGS1 vs Vycor 7913: properties

JGS1Vycor 7913

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

72 GPa10.4 Msi
67 GPa9.7 Msi

Shear Modulus

31 GPa4.5 Msi
28 GPa4.1 Msi

Bulk Modulus

37 GPa5.4 Msi
36 GPa5.2 Msi

Poisson's Ratio

0.17
0.19

Flexural Strength

67 MPa9.7 ksi
65 MPa9.4 ksi

Shear Strength

70 MPa10.2 ksi
60 MPa8.7 ksi

Fracture Toughness (K_IC)

0.75 MPa·√m0.68 ksi·√in
0.72 MPa·√m0.66 ksi·√in

Hardness, Vickers

750 HV
620 HV

Hardness, Knoop

600 HK
530 HK

Same in both: Tensile Strength (Ultimate) 50 MPa7.3 ksi · Elongation at Break 0% · Compressive Strength 1,100 MPa160 ksi · Hardness, Mohs 6

Physical

Density and transition temperatures.

Density

2.2 g/cm³0.08 lb/in³
2.18 g/cm³0.08 lb/in³

Melting Point (Solidus)

1,713°C3,115 °F
1,500°C2,732 °F

Refractive Index

1.459
1.458

Light Transmission

93%
91%

Same in both: Porosity 0%

Thermal

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

Thermal Conductivity

1.4 W/m·K0.8 BTU/hr·ft·°F
1.4 W/m·K0.78 BTU/hr·ft·°F

Specific Heat Capacity

740 J/kg·K0.18 BTU/lb·°F
750 J/kg·K0.18 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

0.55 µm/m·K0.31 µin/in·°F
0.8 µm/m·K0.44 µin/in·°F

Max Service Temperature (continuous)

1,050°C1,922 °F
900°C1,652 °F

Same in both: Min Service Temperature -200°C-328 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

1×10¹⁶ Ω·m3.94×10²³ µΩ·in
1×10¹³ Ω·m3.94×10²⁰ µΩ·in

Dissipation Factor (1 MHz)

1×10⁻⁴
8×10⁻⁴

Volume Resistivity

1×10¹⁸ Ω·cm
1×10¹⁵ Ω·cm

Same in both: Dielectric Strength 30 kV/mm762 V/mil · Dielectric Constant (1 MHz) 3.8

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Corrosion Resistance 95 / 100

Manufacturability

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

Machinability

12 / 100
18 / 100

Polishability

98 / 100
92 / 100

Sintering / Firing Temperature

1,800°C3,272 °F
1,200°C2,192 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

55 MJ/kg23,646 BTU/lb
60 MJ/kg25,795 BTU/lb

Embodied Water

40 L/kg4.8 gal/lb
200 L/kg24 gal/lb

Same in both: Embodied Carbon (primary production) 4.5 kg CO₂/kg · Typical Recycled Content 0%

Common Calculations

Ratios derived from the values above.

Specific Stiffness (E / density)

32.7 MN·m/kg
30.7 MN·m/kg

Thermal Shock Resistance Index

2
1

Same in both: Specific Strength (UTS / density) 23 kN·m/kg · Thermal Diffusivity 0.8 mm²/s

Strength versus weight

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

501002005002.533.5Density (g/cm³)Yield strength (MPa) — log scale

Manufacturing and finishing

CapabilityJGS1Vycor 7913
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

JGS1 vs Vycor 7913 — frequently asked

What is the difference between JGS1 and Vycor 7913?

JGS1 and Vycor 7913 are both glass grades. JGS1 is harder — 750 HV against 620 HV for Vycor 7913 — which matters for wear surfaces and threads. JGS1 is stiffer (72 GPa vs 67 GPa) and JGS1 runs hotter in service (1,050°C vs 900°C continuous).

Which is cheaper, JGS1 or Vycor 7913?

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

Which is easier to machine, JGS1 or Vycor 7913?

Vycor 7913. Its machinability rates poor (18/100) against not recommended (12/100) for JGS1.

Ready to make it?

Upload a CAD file and FabDigit prices the part in JGS1 and Vycor 7913 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.