Intergranular fracture in forgings of steel 09Kh15N8Yu

Autor: G. A. Zheltova, A. P. Akshentseva, A. L. Belinkii
Rok vydání: 1980
Předmět:
Zdroj: Metal Science and Heat Treatment. 22:422-425
ISSN: 1573-8973
0026-0673
DOI: 10.1007/bf00693647
Popis: 1. Intergranular fracture of parts of the rotor of separators made of steel 09Kh15N8Yu occurs in forgings contaminated with A1N of grade 4-5 and TiN of grade 1-2. Forgings with a normal fracture contain only TiN of grade 2-3. 2. The reason for intergranular fracture in forgings of steel 09Kh15N8Yu is overheating of the ingots to 1230–1250° (furnace temperature) during heating for forging and extrusion, accompanied by an increase of the original austenite grain size to grade −1, 0, and 1 and precipitation of dispersed particles of A1N and TiN in austenite grain boundaries. 3. To eliminate rejects for intergranular fracture we recommend a new procedure for heating ingots for forging and extrusion — to 1150±10° (furnace temperature) for forging and to 1180° for extrusion, with holding for 3 and 2 h, respectively. 4. The susceptibility of steel 09Kh15N8Yu to overheating depends to a considerable extent on the deoxidation procedure during melting and pouring, and thus on the number of nonmetallic inclusions of A1N and TiN.
Databáze: OpenAIRE