Understanding Pounds per Cubic Inch to Tonnes per Cubic Meter Conversion
The pound per cubic inch (lb/in3) is a dense imperial unit for metals and compact solids, while the tonne per cubic meter (t/m3) is a metric bulk-density unit that is numerically identical to grams per cubic centimeter. Converting between them is common in international metallurgy, mining, and materials engineering, where a US datasheet in lb/in3 must be compared against SI figures. Because 1 t/m3 equals 1 g/cm3, the result also gives density relative to water's 1 t/m3.
Conversion Formula
To convert pounds per cubic inch to tonnes per cubic meter, multiply by this factor:
Step-by-Step Example
Convert 25 pounds per cubic inch to tonnes per cubic meter.
How to Convert Pounds per Cubic Inch to Tonnes per Cubic Meter
Use the fixed factor to move an imperial density into metric bulk-density units.
- Record your value: Note the density in pounds per cubic inch, such as 25 lb/in3.
- Multiply by 27.6799: Since 1 lb/in3 = 27.6799 t/m3, this rescales mass and volume together.
- Calculate: 25 × 27.6799 = 691.998.
- Result: 25 lb/in3 equals about 691.998 t/m3 (equal to 691.998 g/cm3).
pounds per cubic inch to tonnes per cubic meter conversion table
| pounds per cubic inch (lb/in3) | tonnes per cubic meter (t/m3) |
|---|---|
| 0 | 0 |
| 1 | 27.6799 |
| 2 | 55.35981 |
| 3 | 83.03971 |
| 4 | 110.7196 |
| 5 | 138.3995 |
| 6 | 166.0794 |
| 7 | 193.7593 |
| 8 | 221.4392 |
| 9 | 249.1191 |
| 10 | 276.799 |
| 15 | 415.1986 |
| 20 | 553.5981 |
| 25 | 691.9976 |
| 30 | 830.3971 |
| 40 | 1107.196 |
| 50 | 1383.995 |
| 60 | 1660.794 |
| 70 | 1937.593 |
| 80 | 2214.392 |
| 90 | 2491.191 |
| 100 | 2767.99 |
| 150 | 4151.986 |
| 200 | 5535.981 |
| 250 | 6919.976 |
| 300 | 8303.971 |
| 400 | 11071.96 |
| 500 | 13839.95 |
| 600 | 16607.94 |
| 700 | 19375.93 |
| 800 | 22143.92 |
| 900 | 24911.91 |
| 1000 | 27679.9 |
| 2000 | 55359.81 |
| 3000 | 83039.71 |
| 4000 | 110719.6 |
| 5000 | 138399.5 |
| 10000 | 276799 |
| 25000 | 691997.6 |
| 50000 | 1383995 |
| 100000 | 2767990 |
| 250000 | 6919976 |
| 500000 | 13839950 |
| 1000000 | 27679900 |
What is the Pound per Cubic Inch?
The pound per cubic inch is a US customary and imperial unit of mass density, giving the number of avoirdupois pounds packed into one cubic inch. Because a cubic inch is tiny, this unit yields large numbers and is reserved for very dense materials such as metals.
Definition
One pound per cubic inch equals one avoirdupois pound (0.45359237 kg) in a volume of one cubic inch (1.6387064×10⁻⁵ m³). The result is:
Since an inch is exactly 0.0254 m and a pound exactly 0.45359237 kg, the factor 27679.9047... kg/m³ is exact.
Origin and History
Like other Anglo-American density units, it combines the avoirdupois pound with the cubic inch, a fine-grained volume long used in machining and metalworking. It became a favored unit in metallurgy and mechanical engineering, where compact, high-density samples are measured.
Law and Notable Facts
The defining pound and inch were fixed exactly by the 1959 international yard and pound agreement. A striking fact: one pound per cubic inch is about 27.68 times the density of water, so almost every everyday liquid has a density well below 0.1 lb/in³, making the unit practical mainly for solids and metals.
Real-World Examples and Conversions
Aluminum is about 0.098 lb/in³, steel about 0.284 lb/in³, lead about 0.410 lb/in³, and gold about 0.698 lb/in³. Water is only about 0.0361 lb/in³. To convert to kilograms per cubic meter, multiply by 27679.9; to grams per cubic centimeter, multiply by 27.6799.
What is the Tonne per Cubic Meter?
The tonne per cubic meter is a metric unit of mass density, giving the number of metric tonnes of mass contained in one cubic meter of volume. It is common in civil engineering, mining, and bulk-materials handling, where masses are large.
Definition
One tonne per cubic meter equals one metric tonne (1000 kilograms) spread over one cubic meter. In SI base units:
This makes the tonne per cubic meter numerically equal to the kilogram per liter and to the gram per cubic centimeter, so pure water is very close to 1 t/m³.
Origin and History
The metric tonne (1000 kg) was adopted alongside the metric system to handle industrial-scale masses, and pairing it with the cubic meter—the coherent SI unit of volume—produced a convenient large-scale density unit. It became standard in continental European engineering practice during the nineteenth and twentieth centuries.
Law and Notable Facts
The tonne is accepted for use with the SI, though "t/m³" is a derived combination rather than a coherent SI unit itself. A handy fact: because 1 t/m³ equals 1 kg/L, an engineer's "specific gravity" of a material relative to water reads directly as its density in t/m³.
Real-World Examples and Conversions
Fresh water is about 1.00 t/m³ and seawater about 1.025 t/m³. Ordinary structural concrete runs roughly 2.4 t/m³, while structural steel is about 7.85 t/m³. Dry loose sand is around 1.6 t/m³. To convert to pounds per cubic foot, multiply by 62.43.
Frequently Asked Questions
How many tonnes per cubic meter are in a pound per cubic inch?
One lb/in3 equals about 27.6799 t/m3. This reflects the large density of a full pound packed into a single cubic inch.
Is a tonne per cubic meter the same as a gram per cubic centimeter?
Yes, numerically. 1 t/m3 = 1 g/cm3 = 1,000 kg/m3, so the same value describes both, making comparison with water (1 t/m3) straightforward.
How do I convert tonnes per cubic meter back to pounds per cubic inch?
Multiply the t/m3 value by 0.03612729. For example, 27.6799 t/m3 returns 1 lb/in3.
Where is this conversion applied?
It is used in mining, metallurgy, and international materials engineering when converting US density specs in lb/in3 to metric bulk density.
What is 5 pounds per cubic inch in t/m3?
Multiply 5 by 27.6799 to get about 138.400 t/m3.
People also convert
Complete pounds per cubic inch conversion table
| Unit | Result |
|---|---|
| kilograms per cubic meter (kg/m3) | 27679.9 kg/m3 |
| grams per cubic centimeter (g/cm3) | 27.6799 g/cm3 |
| grams per milliliter (g/mL) | 27.6799 g/mL |
| grams per liter (g/L) | 27679.9 g/L |
| milligrams per milliliter (mg/mL) | 27679.9 mg/mL |
| kilograms per liter (kg/L) | 27.6799 kg/L |
| tonnes per cubic meter (t/m3) | 27.6799 t/m3 |
| pounds per cubic foot (lb/ft3) | 1728 lb/ft3 |
| pounds per cubic yard (lb/yd3) | 46656 lb/yd3 |
| pounds per US gallon (lb/gal) | 231 lb/gal |
| ounces per cubic inch (oz/in3) | 16 oz/in3 |
| ounces per US gallon (oz/gal) | 3696 oz/gal |
| slugs per cubic foot (slug/ft3) | 53.70788 slug/ft3 |