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COE Checker

Check coefficient of expansion compatibility between glass types to prevent cracking.

Inputs

x10⁻⁷/°C

e.g. 90 for Bullseye, 96 for Spectrum

x10⁻⁷/°C

Results

COE Difference

2.0 x10⁻⁷/°C

Compatible

Yes

Excellent compatibility — COE difference within 3

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Tips

1
Even small COE mismatches can cause delayed stress cracking weeks after firing
2
Always test compatibility with a small sample before committing to a large piece

Open formula

ΔCE = |COE₁ - COE₂|
Compatible if ΔCE < threshold

Compares thermal expansion coefficients. Mismatched COE causes stress cracking.

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