METALPAK, CPPAK & EXPAK Specifications...

METALPAK version 1.10

Is founded primarily upon extensive data collected and summarized by the National Institute of Standards and Technology (NIST), with some additional reference data from the Thermophysical Properties Research Center at Purdue University and the National Physical Laboratory in the UK.

METALPAK includes properties of 14 metals:

	Aluminum
	Chromium
	Copper
	Gold
	Iron
	Nickel
	Niobium
	Palladium
	Platinum
	Platinum
	Silver
	Tantalium
	Titanium
	Tungsten

Fundamental properties calculated by METALPAK are

	Specific Heat
	Thermal Expansivity
	Electrical Resistivity
	Thermal Conductivity

For convenient use in engineering applications, derived properties are also calculated:

	Thermal Diffusivity
	Enthalpy
	Integrated length change
	Thermal Conductivity integral

The temperature range for all metal properties is 1 to 300 K. Only normal state properties are calculated for superconductors. Mechanical properties are not included.

Theoretical basis

The electrical resistivity and thermal conductivity in any elemental metal at low temperature are primarily determined by impurities and/or lattice dislocations.

METALPAK uses the method pioneered at NIST for characterizing the impurity/dislocation content of any given sample by a single electrical measurement of "RRR" (the residual resistivity ratio). Such sample characterization will not be accurate for all metallurgical preparation processes, especially those which introduce a unique orientation in the grain structure, but it may be a reasonable first approximation. Cryodata extended the NIST work by developing METALPAK equations which accurately reproduce the available reference data as a function of RRR. The equations are then used to predict properties for an arbitrary RRR supplied by the user. For those metals where reference property data are scarce, the equations are scaled to yield credible properties estimates.

A technical paper describing the basis equations is available to those who may be interested.

For aluminum, copper, and silver, METALPAK also calculates magnetoresistance and related field-dependent properties from NIST data.

METALPAK will likely be an important addition to your library of low temperature standard reference data and Cryodata is not aware of comparable reference program is available from NIST or other sources.

CPPAK 1.20 and EXPAK 1.20

Related to METALPAK are the CPPAK and EXPAK programs which calculate specific heats and thermal expansivities, respectively, of a number of materials. For elemental metals, these properties are also available in METALPAK, with improved accuracy in some cases.

However, CPPAK includes specific heats which are not in METALPAK for:

	Beryllium
	Bismuth
	Cadmium
	Constantan
	Diamond
	Germanium
	Glass
	Graphite
	Ice
	Magnesium
	Mercury
	Molybdenum
	Monel
	Pyrex
	Quartz
	Rhodium
	Rubber
	Silicon
	Sodium
	Teflon
	Zinc

EXPAK includes expansivity data which are not in METALPAK for:

	11 ferrous alloys
	2 cobalt alloys
	2 nickel alloys
	4 aluminum alloys
	Be-copper
	Beryllium
	Brass
	Germanium
	Ice
	Indium Antimonide
	Silicon
	Teflon
	Zinc