Nkk Corporation

Burlington Northern Railroad Company

Masahiro Ueda

Yoshio Saito

Akio Fujibayashi

Tsunemi Wada

Kozo Fukuda

Hiroaki Sato

Kiyotaka Morioka

Toyokazu Teramoto

Yuzuru Kataoka

Takao Gino

Shinichi Nagahashi

Jun Furukawa

Hideyuki Yamanaka

Tomoo Horita

Atsushi Ito

Gordon O Besch

Tetsunari Ide

Mashiro Ueda

Yazuru Kataoka

John A Hovland

A high-strength, damage-resistant rail characterized by essentially consists of 0.60 to 0.85 wt. % of C, 0.1 to 1.0 wt. % of Si, 0.5 to 1.5 wt. % of Mn, not more than 0.035 wt. % of P, not more than 0.040 wt. % of S, and not more than 0.05 wt. % of Al, a balance being Fe and indispensable impurity. The rail comprises corner and head side portions having a Brinell hardness H.sub.B of 341 to 405 and a head top portion having a hardness which is not more than 0.9 of the Brinell hardness of the corner and head side portions.

High-strength, damage-resistant rail

A method for heat-treating a steel rail head, which comprises: heating a steel rail head to the austenization temperature; then, cooling the rail head by means of a hot water jet until a surface temperature of the rail head decreases to a temperature not below 420.degree. C.; and then cooling the rail head by means of an air jet at least to the pearlite transformation temperature, thereby transforming the structure of a surface portion of the rail head into a uniform and fine pearlite structure. The above-described method includes a method in which the rail head is previously cooled by means of a water spray until the surface temperature of the rail head decreases to a temperature not below 530.degree. C. prior to the cooling of the rail head by means of the above-mentioned hot water jet.

Method for heat-treating steel rail head

Growing community of inventors

Kanagawa, Japan

Takao Gino