Mechanical properties, wear, and corrosion of boronized N80 tube steel

The effect of boronizing on the mechanical properties, wear, and corrosion of boronized N80 tube steel is studied. A dual-phase boride layer consisting of the FeB and F2B phases is formed on the surface of steel substrate within the hardness range 1220–1340 HV. A special setup was designed to use smaller amounts of the boriding agent and accelerate the process of cooling of the pipe. In order to meet the tensile properties of N80 steel required by the API SPEC 5L, four cooling methods were employed. The procedure of fan cooling with a graphite bar inside the boriding agent resulted in the highest mechanical properties in accordance with the mechanical properties of the API SPEC 5L. The boronized N80 steel reveal a high wear resistance under the conditions of dry sliding and excellent corrosion resistance in the as-received oil-field water from the Jilin oil field, Northeast China.