Convert Square millimetres per hour to Square inches per second

Convert Square millimetres per hour (mm²/h) to Square inches per second (in²/s) instantly and accurately.

Square millimetres per hour (mm²/h)
Square inches per second (in²/s)

Conversion Formula

in²/s = mm²/h × 4.305564167e-7

About Square millimetres per hour

The square millimetre per hour (mm²/h) equals 1/3 600 000 000 m²/s, the smallest practical thermal diffusivity unit. It is used in very slow heat-transfer processes such as diffusion through frozen soils or phase-change materials studied over many hours. Heavy clay soils can show diffusivity values of 1-2 mm²/h. 1 mm²/h = 1e-6/3600 m²/s.

About Square inches per second

The square inch per second (in²/s) equals 6.4516 × 10⁻⁴ m²/s, used in high-speed thermal analyses such as ballistic impact heating, explosive detonation studies, and rapid induction heating of steel billets. Values for high-conductivity copper alloys reach ≈1-2 in²/s; for mild steel ≈0.3 in²/s. 1 in²/s = 0.00064516 m²/s = 3600 in²/h.

Quick Reference Table

Square millimetres per hour (mm²/h)Square inches per second (in²/s)
1 mm²/h4.306 × 10-7 in²/s
2 mm²/h8.611 × 10-7 in²/s
5 mm²/h2.153 × 10-6 in²/s
10 mm²/h4.306 × 10-6 in²/s
25 mm²/h1.076 × 10-5 in²/s
50 mm²/h2.153 × 10-5 in²/s
100 mm²/h4.306 × 10-5 in²/s

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