Patent · US Expired

Method for the preparation of a hardening salt in piece form and product

US5453109A · kind A · utility

0Cited by

3References

13Claims

0Family size

Assignee

Durferrit GmbH Thermotechnik · DE

Inventors

Peter Schalke · Seligenstadt, DE
Eberhard Mueller · Edmonton, CA
Matthias Kremer · Wiesbaden, DE
Georg Wahl · Rodenbach, DE

Key dates

Filing date	Jul 13, 1994
Grant date	Sep 26, 1995
Priority date	—
Expiry date	Jul 13, 2014

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC21D1/46
WIPO fieldMaterials, metallurgy
WIPO sectorChemistry

Abstract

A method for the preparation of a salt mixture useful for hardening steel parts, including of potassium cyanate, potassium carbonate and sodium carbonate, wherein 2.2 to 2.3 moles of urea is first reacted with 1 mole of potassium carbonate to form potassium cyanate. The escaping ammonia is converted with formaldehyde into hexamethylenetetramine. The reaction product, which is potassium cyanate and potassium carbonate, is ground, mixed with powdered sodium carbonate and pressed at between 80.degree. and 230.degree. C. into shaped pieces.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.