BS 4789:1972

This British Standard covers the requirements for fabricated ceramic parts suitable for joining to metal to form the envelopes for electronic tubes (Category 1) and for special materials (Categories 2 and 3) which are in addition suitable for high power microwave windows.

It specifies the limits for values of properties for the different categories. For special applications when a purchase order calls for a requirement different from this standard the purchase order shall prevail.

This standard makes reference to and should be read in conjunction with BS 1598:1964.

NOTE The titles of the British Standards referred to in this standard are listed on page iii.

Lists the definitions, properties and test methods and gives the test schedules for type, batch and component testing of three categories of ceramic material suitable for use in electronic tube envelopes.