AIST>Network Database System for Thermophysical Property Data

Network Database System for Thermophysical Property Data is developed and run by AIST, and is available for free. Thermophysical properties data (ex. Thermal conductivity, thermal diffusivity, heat capacity, density, surface tension and vapor pressure) for liquid, solid and melts are stored in this database.

Browsing DB by Web browser: TPDS-web

- TPDS-web operation manual -



TPDS-web/full is the software to browse Network Database System for Thermophysical Property Data via web browser. Therefore, these data structures are the same. In our database, material data and property data are maneged separately and it is characterized by material classification using hierarchical structure and data reliability classification for property data. By understanding these characteristics, you can utilize TPDS-web/full more effectively. This section describes it in detail.

1.1 Material classification and hierarchical structure

In our database, materials fall into 8 classifications according to chemical property or phase state and are organized systematically using hierarchical structure. In the case of solid which is most diverse, classification example is as Table 1. The folder colors in the table corresponds to those in TPDS-web/full.
Table 1 Material classification standards and hierarchical structure

1st stratum


Classification by perspective of the community of study or technology

(also by phase state at ordinary temperatures and pressures)

2nd stratum


Material classification

Example: Metal, Ceramics, Semiconductor

3rd stratum
(material class 1)


Material group 1

Example: Oxide, Carbide (in case of ceramics), Transition metal, p-block metal, Alkali metal (in case of metal)

4th stratum
(material class 2)


Compound name
Classification by chemical composition of major elements, IUPAC name or CAS Registry number

Example: Aluminum, Carbon, Silicon carbide

5th stratum
(material class 3)


Material name 1
Classification by crystalline or material structure

Example: Silicon single crystal, Silicon polycrystal, Polycrystalline alumina

6th stratum


Material name 2
Classification by element composition, porosity or chemical purity

Example: product name, grade, standard name (such as SUS304), reference material name

7th stratum


Lot name
Classification by heat treat or characters

The classification name is determined by the company provides samples or the person who collected or registered the data

8th stratum
(measured sample)


Sample name
Classification by measured sample shape or surface treatment condition

The classification name is determined by the company provides samples or the person who collected or registered the data


1.2 3 Category of property data (Data Category)

There are 3 categories of Type (how to get the data), Traceability and Authorization (data authentication state) according to property data type or reliability. Table 2, 3 and 4 shows each category.

Table 2. Peoperty data category (Type)




Measured value


The data derived from physical law based on measured value
Example: Specific heat capacity derived from temperature change of enthalpy, density at room temperature and at other temperature derived from coefficient of expansion.


The data derived from comparing, synthesizing and fitting previous data with instrument data (on the same thermophysical property)
The equation data derived from statistical processing for a large number of reference data


The data derived from numeric calculation such as first principle molecular dynamics


The theoretically-derived property data



Table 3. Property data category (Traceability)



International Standard

International standard value

National Standard

National standard value

Traceable Measurement

The value derived from traceable measurement to national standards such as using the measurement system is proofread based on authentication standard materials

Industrial Standard

The measured value in line with industry standard (such as ISO, JIS)



Table 4. Property data category (Authorization)



Reviewed Journal

The data in manuscripts reviewed by referees or editional committees of academic journals


The data recommended by society, public institutions, company or scientists for data evaluation


The value authenticated by the traceability to national standards


The data evaluated by material suppliers under their responsibility


The authenticated data on the grounds other than listed above


Unrecognized data or the data is not clear whether it is authenticated or not

1.3 User project management

In our database, property data and users are belong to any project, and access permit of graph, table and equation data is managed on a per-project basis. For example, if you registerd, you will get the login account and password and will be able to access to the released data for domestic organization.

1.4 Characteristics and usage of thermophysical property database

You can get a good overview of the property of allogeneic material and expand an understanding of materials, by using records and displays according to the material classification or hierarchical structure. If you understand material structure and property and want to use only concrete property, it is more useful than search function. However, since the property data category shows the data type or reliability, if you need only reliable data, you can hit only appropriate property data by using advanced search function.

Browsing system by web browser


It is possible to use simple search or data comparison of the browse system without depending on a certain OS or browser.

Data Update Info.