US2041635A - Steel for railroad rails, wheel tires, plankpiles and other objects which are subjected to heavy wear - Google Patents

Description

Patented May 19, 1936 UNITED STATES PATENT OFFICE STEEL FOR RAILROAD RAILS, WHEEL TIRES, PLANKPILES AND OTHER OBJECTS WHICH ARE SUBJECTED TO HEAVY WEAR No Drawing. Originalapplication December 11,

1931, Serial No. 580,500.

Divided and this application February 13, 1935, Serial No. 6,392. In Germany December 12, 1930 2 Claims.

The invention refers to a further improvementthe following values have been found for the of the steel for railroad rails, wheel tires, plankpiles and other objects which are subjected to heavy wear as claimed and. described in my copending application Serial No. 580,500 from which the present case is a division.

In said copending application it has been suggested to use for the mentioned purpose a steel containing about 0.05 to 0.2% of carbon, about 0.08 to 0.25% of phosphorus, about 0.1 to 0.6% of silicon, about 0.6 to 1.6% of manganese, about 0.25 to 1% of copper and the balance substantially iron. Now it has been found that by an addition of chromium a further improvement of the wear resistance and the resistance against shock can be obtained. Said improved resistance against shock and impact stresses of a steel containing carbon, phosphorus silic-cn, manganese and copper in the proportions above described and in addition thereto from an effective amount to about 1.5% of chromium is especially to be observed with objects of larger extensions. The chromium content is able to improve the notched bar tenacity even in the inner zones of large cross-sections and simultaneously to increase the wear resistance. Thus the addition of chromium is adapted to cause a. further improvement of the qualities obtained by the-composition described in the copending application. As in my prior composition the sulphur content is preferably kept low so as to lie between a trace and about 0.12%.

The favourable results obtained by the invention are to be seen from the following experi-' ments in which normal carbon steels and those corresponding to my copending application Serial No. 580,500 on the one hand are compared with compositions corresponding to the-present invention on the other hand:

Said steels were subjected to the following tests:

a. In samples of 10 x 10 x mm. with a round notch of a width of 2 mm. and a depth of 5 mm.

notched bar tenacity:

Mkg/cm Steel 1 3 Steel 2 10 Steel 3 10 Steel 4 11 b. In order to determine the wear on the Spindel-machine the length of the chord was determined as average value obtained with four pieces at a pressure of 5 kg. The total number of revolutions was 250; 25 revolutions were effected per minute. The following values were measured:

Mm. Steel 1 43 Steel 2 41 Steel 3--.. 40 Steel 4 38 I Grms. Steel 1 1.4 Steel 2 1.0 Steel 3 0.9 Steel 4- 0.8

What I claim and desire to secure by Letters Patent of the United States of America is:

1. A steel for railroad rails, wheel tires, plankpiles and other objects which are subjected to heavy wear, said steel containing about 0.05 to 0.20% of carbon, about 0.08 to 0.25% of phosphorus, about 0.1 to 0.6% of silicon, about 0.6 to 1.6% of manganese, from an effective amount to about 1.5% of chromium and about 0.25 to 1% of copper and the balance substantially iron.

2. A steel for railroad rails, wheel tires, plankpiles and other objects, which are subjected to heavy wear, with a sulphur content of from trace to about 0.12%, said steel containing about 0.05 to 0.20% of carbon, about 0.08 to 0.25% phosphorus, about 0.1 to 0.6% of silicon, about 0.6 to 1.6% of manganese, from an effective amount to about 1.5% of chromium and about 0.25 to 1% oi. copper, and the balance substantlally iron.

ERT BUCEHOLTZ.