ASTM A227 Spring Steel vs. R04295 Alloy

ASTM A227 spring steel belongs to the iron alloys classification, while R04295 alloy belongs to the otherwise unclassified metals. There are 17 material properties with values for both materials. Properties with values for just one material (14, in this case) are not shown.

For each property being compared, the top bar is ASTM A227 spring steel and the bottom bar is R04295 alloy.

ASTM A227 Spring Steel UNS R04295 Niobium-Hafnium Alloy

Metric UnitsUS Customary Units

Mechanical Properties

Elastic (Young's, Tensile) Modulus, GPa		190
Elastic (Young's, Tensile) Modulus, GPa		100

Elongation at Break, %		12
Elongation at Break, %		22

Poisson's Ratio		0.29
Poisson's Ratio		0.38

Shear Modulus, GPa		72
Shear Modulus, GPa		37

Tensile Strength: Ultimate (UTS), MPa		1720 to 2220
Tensile Strength: Ultimate (UTS), MPa		410

Tensile Strength: Yield (Proof), MPa		1430 to 1850
Tensile Strength: Yield (Proof), MPa		300

Thermal Properties

Latent Heat of Fusion, J/g		250
Latent Heat of Fusion, J/g		300

Specific Heat Capacity, J/kg-K		470
Specific Heat Capacity, J/kg-K		260

Thermal Expansion, µm/m-K		12
Thermal Expansion, µm/m-K		7.2

Otherwise Unclassified Properties

Density, g/cm³		7.8
Density, g/cm³		9.0

Embodied Water, L/kg		46
Embodied Water, L/kg		950

Common Calculations

Resilience: Ultimate (Unit Rupture Work), MJ/m³		200 to 260
Resilience: Ultimate (Unit Rupture Work), MJ/m³		84

Stiffness to Weight: Axial, points		13
Stiffness to Weight: Axial, points		6.3

Stiffness to Weight: Bending, points		24
Stiffness to Weight: Bending, points		17

Strength to Weight: Axial, points		61 to 79
Strength to Weight: Axial, points		13

Strength to Weight: Bending, points		41 to 48
Strength to Weight: Bending, points		14

Thermal Shock Resistance, points		55 to 71
Thermal Shock Resistance, points		40

Alloy Composition

Carbon (C), %		0.45 to 0.85
Carbon (C), %		0 to 0.015

Hafnium (Hf), %		0
Hafnium (Hf), %		9.0 to 11

Hydrogen (H), %		0
Hydrogen (H), %		0 to 0.0015

Iron (Fe), %		97.4 to 99.1
Iron (Fe), %		0

Manganese (Mn), %		0.3 to 1.3
Manganese (Mn), %		0

Niobium (Nb), %		0
Niobium (Nb), %		85.9 to 90.3

Nitrogen (N), %		0
Nitrogen (N), %		0 to 0.010

Oxygen (O), %		0
Oxygen (O), %		0 to 0.025

Phosphorus (P), %		0 to 0.040
Phosphorus (P), %		0

Silicon (Si), %		0.15 to 0.35
Silicon (Si), %		0

Sulfur (S), %		0 to 0.050
Sulfur (S), %		0

Tantalum (Ta), %		0
Tantalum (Ta), %		0 to 0.5

Titanium (Ti), %		0
Titanium (Ti), %		0.7 to 1.3

Tungsten (W), %		0
Tungsten (W), %		0 to 0.5

Zirconium (Zr), %		0
Zirconium (Zr), %		0 to 0.7