Steel weighs about 7.85 g/cm³ (0.284 lb/in³) and melts at roughly 1,415 to 1,520 °C; 6061 aluminium is 2.70 g/cm³ (0.098 lb/in³) and melts between 582 and 652 °C. Steel is almost exactly three times as heavy as aluminium.

This chart gives the nominal density and the melting point or melting range of 60 metals and alloys you meet in a machine shop: pure metals, carbon and alloy steel, tool steel, stainless, cast iron, aluminium, copper alloys, titanium, nickel alloys, magnesium, zinc die-cast and low-melt solders. Density is shown four ways (g/cm³, kg/m³, lb/in³ and lb/ft³) and temperature in °C and °F. For an alloy, the first figure is the solidus (where melting starts) and the second the liquidus (where it is fully liquid). Type a grade into the search box, pick a family, tap a column heading to sort, or switch the chart to metric or imperial only. Use the density to work out stock weight, check shipping weights or identify an unknown part.

Density and melting point chart

also known as g/cm³ Densitykg/m³ lb/in³ Densitylb/ft³ °C (solidus–liquidus) °F (solidus–liquidus) Notes
MagnesiumMg, purePure metals1.7381,7380.0628108.56501,202Lightest structural metal. Fine chips and dust burn: never use water on a magnesium fire.
AluminiumAl, pure, aluminumPure metals2.7002,7000.0975168.6660.31,221Pure aluminium; alloys are slightly lighter or heavier (2,660 to 2,810 kg/m³).
TitaniumTi, purePure metals4.5064,5060.1628281.31,6683,034About 57% of the weight of steel.
ZincZn, purePure metals7.1347,1340.2577445.4419.5787Galvanising coating; zinc fumes from welding galvanised steel are harmful.
ChromiumCr, purePure metals7.1507,1500.2583446.41,9073,465Used as plating and as an alloying element in stainless and tool steel.
TinSn, pure, white tinPure metals7.2877,2870.2633454.9231.9449Base of most solders and of tin bronze.
IronFe, purePure metals7.8747,8740.2845491.61,5382,800Pure iron; steels are 7,700 to 8,000 kg/m³ depending on alloy.
CobaltCo, purePure metals8.9008,9000.3215555.61,4952,723Binder in carbide tools and an alloying element in M42 HSS and superalloys.
NickelNi, purePure metals8.9088,9080.3218556.11,4552,651Base of Inconel, Monel and Hastelloy.
CopperCu, purePure metals8.9608,9600.3237559.41,084.61,984Pure element. Commercial C110 copper is listed under copper alloys.
BismuthBi, purePure metals9.7809,7800.3533610.5271.4521Expands slightly when it freezes; used in low-melt fixturing alloys.
MolybdenumMo, pure, molyPure metals10.2210,2200.3692638.02,6234,753Refractory metal for furnace parts and EDM wire; alloying element in 4140 and HSS.
SilverAg, purePure metals10.4910,4900.3790654.9961.81,763Base of silver brazing alloys.
LeadPb, purePure metals11.3411,3400.4097707.9327.5622Ballast and radiation shielding; the "L" in 12L14 free-cutting steel.
TungstenW, pure, wolframPure metals19.3019,3000.6973Weight Calculator: 0.6971,204.93,4226,192Highest melting point of any metal. TIG electrodes and balance weights.
GoldAu, purePure metals19.3219,3200.69801,206.11,064.21,948Almost the same density as tungsten.
1018 steelAISI 1018, C15, mild steel, EN32BCarbon and alloy steel7.8507,8500.2836Weight Calculator: 0.284490.1≈1,480–1,520≈2,696–2,768Low-carbon bright bar. Datasheets give 7,870 kg/m³; the 0.25% difference is inside normal variation.
1045 steelAISI 1045, C45, EN8 (nearest)Carbon and alloy steel7.8507,8500.2836Weight Calculator: 0.284490.1≈1,430–1,495≈2,606–2,723Medium-carbon shafting steel.
4140 alloy steelAISI 4140, 42CrMo4, EN19, chrome molyCarbon and alloy steel7.8507,8500.2836Weight Calculator: 0.284490.1≈1,415–1,495≈2,579–2,723Chrome-moly steel for shafts and fixtures, often pre-hardened.
A36 structural steelASTM A36, S275JR, mild steelCarbon and alloy steel7.8507,8500.2836Weight Calculator: 0.284490.1≈1,470–1,515≈2,678–2,759Structural plate and sections.
D2 tool steelAISI D2, 1.2379, SKD11Tool steel7.7007,7000.2782480.7n/pn/pHigh-carbon, high-chromium die steel. Makers rarely publish a melting range; high-carbon tool steels start to melt at roughly 1,300 to 1,450 °C.
H13 tool steelAISI H13, 1.2344, SKD61Tool steel7.8007,8000.2818486.9n/pn/pHot-work steel for die-casting dies. Makers rarely publish a melting range; high-carbon tool steels start to melt at roughly 1,300 to 1,450 °C.
O1 tool steelAISI O1, 1.2510, gauge plateTool steel7.8307,8300.2829488.8n/pn/pOil-hardening gauge plate. Makers rarely publish a melting range; high-carbon tool steels start to melt at roughly 1,300 to 1,450 °C.
A2 tool steelAISI A2, 1.2363, SKD12Tool steel7.8607,8600.2840490.7n/pn/pAir-hardening tool steel. Makers rarely publish a melting range; high-carbon tool steels start to melt at roughly 1,300 to 1,450 °C.
410 stainlessAISI 410, 1.4006, martensiticStainless steel7.7507,7500.2800483.81,480–1,5302,696–2,786Hardenable martensitic stainless; magnetic.
17-4PH stainless630, 1.4542, precipitation hardeningStainless steel7.7807,7800.2811485.71,404–1,4402,559–2,624Density rises slightly after ageing (about 7,810 kg/m³ in H900).
303 stainlessAISI 303, 1.4305, free machiningStainless steel8.0008,0000.2890499.41,400–1,4202,552–2,588Free-machining austenitic stainless.
304 stainlessAISI 304, 1.4301, 18/8, A2Stainless steel8.0008,0000.2890Weight Calculator: 0.29499.41,400–1,4502,552–2,642General-purpose austenitic stainless.
316 stainlessAISI 316, 1.4401, A4, marineStainless steel8.0008,0000.2890Weight Calculator: 0.29499.41,375–1,4002,507–2,552Molybdenum-bearing stainless for marine and chemical use.
Ductile ironSG iron, nodular, 65-45-12, EN-GJSCast iron7.1007,1000.2565443.2≈1,150–1,200≈2,102–2,192Density varies with graphite content (about 7,000 to 7,200 kg/m³).
Grey cast irongray iron, ASTM A48 class 30, EN-GJLCast iron7.2007,2000.2601Weight Calculator: 0.26449.5≈1,150–1,200≈2,102–2,192Density varies with grade (about 6,950 to 7,350 kg/m³).
5083 aluminiumAA 5083, AlMg4.5Mn, aluminumAluminium alloys2.6602,6600.0961166.1591–6381,096–1,180Marine plate and tooling plate.
5052 aluminiumAA 5052, AlMg2.5, aluminumAluminium alloys2.6802,6800.0968167.3607–6491,125–1,200Sheet-metal and marine alloy.
A356 cast aluminiumA356.0, AlSi7Mg, LM25 (nearest), aluminumAluminium alloys2.6802,6800.0968167.3555–6151,031–1,139Sand and permanent-mould casting alloy.
6063 aluminiumAA 6063, AlMg0.7Si, aluminumAluminium alloys2.6902,6900.0972167.9616–6541,141–1,209Architectural extrusions.
6061 aluminiumAA 6061, AlMg1SiCu, H20, aluminumAluminium alloys2.7002,7000.0975Weight Calculator: 0.098168.6582–6521,080–1,206General-purpose machining alloy; the reference for the relative weights in the finder app.
6082 aluminiumAA 6082, AlSi1MgMn, H30, aluminumAluminium alloys2.7002,7000.0975168.6≈575–650≈1,067–1,202European general-purpose alloy. Some datasheets give a lower solidus (about 555 °C).
1100 aluminiumAA 1100, 99.0% Al, aluminumAluminium alloys2.7102,7100.0979169.2643–6571,189–1,215Commercially pure aluminium sheet.
2024 aluminiumAA 2024, AlCu4Mg1, aluminumAluminium alloys2.7802,7800.1004173.5502–638936–1,180High-strength aircraft alloy. Copper makes it heavier than 6061.
7075 aluminiumAA 7075, AlZn5.5MgCu, aluminumAluminium alloys2.8102,8100.1015175.4477–635891–1,175High-strength alloy for moulds and aerospace parts.
Aluminium bronze C954C95400, aluminum bronze, AB1 (nearest)Copper, brass and bronze7.4507,4500.2691465.11,025–1,0401,877–1,904Cast bearing and wear bronze; much lighter than tin bronze.
Beryllium copper C172C17200, BeCu, CW101CCopper, brass and bronze8.2508,2500.2981515.0865–9801,589–1,796Spring and non-sparking tool alloy. Do not breathe the dust from grinding or polishing.
Naval brass C464C46400, CZ112, CW712RCopper, brass and bronze8.4108,4100.3038525.0885–9001,625–1,652Corrosion-resistant brass for marine fittings.
Free-cutting brass C360C36000, CZ121, CW614N, brass 360Copper, brass and bronze8.5008,5000.3071Weight Calculator: 0.307530.6885–9001,625–1,652The standard brass for turned parts.
Bronze (general nominal)generic bronze, Weight Calculator valueCopper, brass and bronze8.8008,8000.3179Weight Calculator: 0.318549.4n/pn/pThe Weight Calculator's nominal "bronze". Real bronzes run from 7,450 to 8,930 kg/m³ and melt between about 850 and 1,060 °C: use a named grade when you can.
Phosphor bronze C510C51000, PB102, CW451KCopper, brass and bronze8.8608,8600.3201553.1975–1,0601,787–1,940Spring and bearing bronze.
Bearing bronze C932C93200, SAE 660, leaded tin bronzeCopper, brass and bronze8.9308,9300.3226557.5855–9771,571–1,791Cast bushing and bearing bronze.
Copper C110 (ETP)C11000, CW004A, electrolytic tough pitchCopper, brass and bronze8.9408,9400.3230Weight Calculator: 0.323558.11,065–1,0831,949–1,981Commercial copper bar and busbar. The low solidus comes from the oxygen it contains.
Titanium 6Al-4V (Grade 5)Ti-6Al-4V, Grade 5, 3.7165Titanium4.4304,4300.1600Weight Calculator: 0.16276.61,604–1,6602,919–3,020The most common titanium alloy.
Titanium Grade 2CP titanium, 3.7035, commercially pureTitanium4.5104,5100.1629281.6≈1,665≈3,029Commercially pure titanium. Melting point is approximate.
Inconel 718alloy 718, UNS N07718, 2.4668Nickel alloys8.2208,2200.2970Weight Calculator: 0.297513.21,260–1,3362,300–2,437Age-hardened superalloy; work-hardens badly when machined.
Inconel 625alloy 625, UNS N06625, 2.4856Nickel alloys8.4408,4400.3049526.91,290–1,3502,354–2,462Corrosion-resistant superalloy.
Monel 400alloy 400, UNS N04400, 2.4360Nickel alloys8.8008,8000.3179549.41,300–1,3502,372–2,462Nickel-copper alloy for marine and chemical parts.
Hastelloy C-276alloy C-276, UNS N10276, 2.4819Nickel alloys8.8908,8900.3212555.01,323–1,3712,413–2,500Highly corrosion-resistant nickel-molybdenum-chromium alloy.
Magnesium AZ31BAZ31, 3.5312, magnesium alloyMagnesium and zinc alloys1.7701,7700.0639110.5605–6301,121–1,166Wrought magnesium plate and bar. Fire risk from fine chips.
Zamak 3ZP3, ZL0400, Zn-Al4, zinc die-castMagnesium and zinc alloys6.6006,6000.2384412.0381–387718–729Most common zinc die-casting alloy.
SAC305 lead-free solderSn96.5Ag3Cu0.5Solders and low-melt alloys7.3807,3800.2666460.7217–220423–428Common lead-free electronics solder.
Sn63Pb37 solder63/37 eutectic tin-leadSolders and low-melt alloys8.4008,4000.3035524.4183361Eutectic: melts at one temperature.
Sn60Pb40 solder60/40 tin-leadSolders and low-melt alloys8.5008,5000.3071530.6183–190361–374Pasty between 183 and 190 °C.
Cerrobend (Bi-Pb-Sn-Cd)Wood's metal type, 158 °F alloySolders and low-melt alloys9.3809,3800.3389585.670158Fixturing and tube-bending alloy; contains lead and cadmium.

≈ = typical or estimated value. n/p = not published (see the note). Densities are at room temperature (about 20 °C). Every density column is worked out from the kg/m³ figure (1 g/cm³ = 0.0361273 lb/in³ = 62.428 lb/ft³). Where a row says Weight Calculator: 0.284, that is the rounded lb/in³ figure our Weight Calculator uses for that material; it is the same kg/m³ value, rounded.

Sources: pure metals from the CRC Handbook of Chemistry and Physics; alloys from ASM International handbooks, MatWeb and makers' datasheets (Copper Development Association, Special Metals, Haynes International, Aluminum Association, stainless steel mills, solder makers), cross-checked against at least two sources. Steel melting ranges are estimated from the iron-carbon diagram and vary with composition. All values are nominal and for guidance only: check critical values against the material standard, the mill certificate or the maker's datasheet.

Compare metals side by side. The Metal Properties Finder & Compare app uses this same data: pick up to three metals, see how much heavier each is than 6061, weigh a bar, plate or tube in each one, and find which metal matches a density you measured.
Open the app

Density vs specific gravity

Density is mass per unit volume. Metric shops use g/cm³ or kg/m³ (1 g/cm³ = 1,000 kg/m³). Imperial shops use lb/in³ for parts and bar, and lb/ft³ for plate and bulk material (there are 1,728 in³ in a cubic foot, so lb/ft³ = lb/in³ × 1,728).

Specific gravity (SG, or relative density) is the density divided by the density of water. It has no units. Water is 1.000 g/cm³, so the specific gravity of a metal is the same number as its density in g/cm³: steel has an SG of about 7.85, aluminium about 2.70. Old handbooks and casting suppliers often list SG instead of density.

lb/in³ = g/cm³ × 0.0361273   |   lb/ft³ = g/cm³ × 62.428   |   kg/m³ = g/cm³ × 1,000
g/cm³ = lb/in³ × 27.680   |   SG = density ÷ density of water (1.000 g/cm³)

Density changes a little with alloy, heat treatment and temperature. Two "steels" can differ by 1 to 2%, cast iron by more because of its graphite, and every metal gets slightly less dense as it warms up and expands. For weights and quotes the nominal values in the chart are close enough; for precision work, use the maker's figure for the exact grade.

Why alloys melt over a range

A pure metal melts at one temperature: aluminium at 660.3 °C, copper at 1,084.6 °C. An alloy is a mix of elements, and the mix does not all melt at once. It starts to melt at the solidus, is a slushy mix of solid and liquid in between, and is fully liquid only at the liquidus. 2024 aluminium, for example, starts to melt at 502 °C, well below its liquidus of 638 °C, because the copper-rich areas in it melt first.

The exception is a eutectic alloy, a mix that melts at one temperature lower than either of its elements. 63/37 tin-lead solder melts at 183 °C, while 60/40 is pasty between 183 and 190 °C.

Why the solidus matters in the shop: heat treating, brazing, hot forming and welding have to stay safely below the solidus, not the liquidus. Overheated aluminium (especially 2xxx and 7xxx alloys) can start melting along its grain boundaries well before it looks soft. For welding temperatures see the Weld Preheat calculator.

How to work out weight from density

Weight is simply volume × density. Work out the volume of the stock in the same units as the density, then multiply. The Weight Calculator does it for plate, round bar and balls; the Metal Properties Finder weighs round bar, flat bar, plate and tube in up to three metals at once.

Round bar: V = π ÷ 4 × D² × L
Flat bar or plate: V = W × T × L
Tube: V = π ÷ 4 × (OD² − ID²) × L, where ID = OD − 2 × wall
Metric: kg = V (mm³) ÷ 1,000,000,000 × density (kg/m³)
Imperial: lb = V (in³) × density (lb/in³)

Worked examples

  • Metric, round bar: 50 mm diameter steel bar, 300 mm long. V = π ÷ 4 × 50² × 300 = 589,049 mm³ = 0.000589 m³. Weight = 0.000589 × 7,850 = 4.62 kg.
  • Imperial, round bar: 2 in diameter 6061 aluminium, 12 in long. V = π ÷ 4 × 2² × 12 = 37.70 in³. Weight = 37.70 × 0.0975 = 3.68 lb (3.69 lb with the rounded 0.098).
  • Metric, plate: 300 × 200 × 20 mm 304 stainless. V = 1,200,000 mm³. Weight = 1,200,000 ÷ 10⁹ × 8,000 = 9.60 kg. The same plate in 6061 would be 3.24 kg.
  • What is this metal? A part weighs 412 g and pushes 52.5 cm³ of water out of a full container. Density = 412 ÷ 52.5 = 7.85 g/cm³: carbon or alloy steel (or stainless, which is within 2%; try a magnet, since 303, 304 and 316 are barely magnetic when annealed).

Shop tips

  • Quick ratios: steel is about 2.9 times as heavy as aluminium, brass about 3.1 times, and titanium 6Al-4V about 56% of steel. Swapping a steel part for 6061 cuts its weight by about two thirds.
  • Lb/in³ for bar, lb/ft³ for plate. A 1 in thick steel plate weighs 490 ÷ 12 = about 40.8 lb per square foot, a handy figure for crane and shelf loads.
  • Copper alloys vary most. Aluminium bronze is 7,450 kg/m³ and bearing bronze 8,930: a 20% difference, so use the exact grade, not "bronze".
  • Magnesium and titanium chips burn. Keep fine chips clean and dry, have a Class D extinguisher, and never use water on a metal fire.
  • Low-melt alloys for fixturing. Alloys such as Cerrobend melt in hot water (70 °C) and can hold thin or odd-shaped parts for machining, then be melted out. They contain lead and cadmium, so handle them with care.
  • Check thermal growth too. Metals with a low melting point usually expand more with heat. Work out the size change with the Thermal Expansion calculator.

Frequently asked questions

Carbon and low-alloy steel is about 7,850 kg/m³, which is 7.85 g/cm³, 0.2836 lb/in³ (usually rounded to 0.284) or 490 lb/ft³. Stainless steels such as 304 and 316 are slightly heavier at about 8,000 kg/m³ (0.289 lb/in³).

Pure aluminium melts at 660.3 °C (1,221 °F). Aluminium alloys melt over a range and start to melt lower: 6061 melts between about 582 and 652 °C (1,080 to 1,206 °F) and 7075 between 477 and 635 °C (891 to 1,175 °F).

Density is mass per unit volume, such as 7.85 g/cm³ or 0.284 lb/in³. Specific gravity is the density divided by the density of water, so it has no units. Because water is 1 g/cm³, the specific gravity of a metal is the same number as its density in g/cm³: steel is about 7.85.

An alloy is a mix of elements that do not all freeze at the same temperature. It starts to melt at the solidus and is fully liquid only at the liquidus; in between it is a slushy mix of solid and liquid. Pure metals and eutectic alloys such as 63/37 solder melt at one temperature.

Work out the volume, then multiply by the density. For a round bar the volume is π ÷ 4 × diameter² × length. A 50 mm steel bar 300 mm long is 589,049 mm³, which is 0.000589 m³; times 7,850 kg/m³ that is 4.62 kg. The Weight Calculator does this for you.