Effect of pack-boriding on the tribological behavior of Hardox 450 and HiTuf Steels

Abstract

In this study, Hardox 450 and HiTuf steels were boronized by pack-boriding method at 800, 900, and 1000∘C for 5 h. The phases, microstructure, hardness, and wear behavior of boride layers formed on the surface of samples were investigated using XRD, SEM, Micro-Vickers hardness testers, and a pin-on-disc tribotester, respectively. XRD analysis showed that both FeB and Fe2B phases were formed in the borided area of Hardox 450 steel, but only Fe2B phase occurred in the boride layer of the HiTuf steel. Micro-Vickers hardness results indicated that the hardness values of the boride layer decreased from the column-shaped structure to towards the matrix in both of Hardox 450 and HiTuf steels. Furthermore, the wear test results showed the coefficients of friction (COF) decreased significantly in the borided samples. The COF of the unborided Hardox 450 steel was reduced considerably from 0.29 to 0.02 by boriding treatment. Similarly, the COF of unborided HiTuf steel was significantly diminished from 0.16 to 0.04 by boriding treatment. In conclusion, the results of this study have indicated that the wear resistance of Hardox 450 and HiTuf steels can be improved by pack-boriding.

Surface characterization of a modified cold work tool steel treated by powder‐pack boronizing

“…Besides, for a better investigation and for the sake of a user‐friendly comparison of the evolution of the surface properties as a function of the prescribed boronizing parameters, Figure 3 is appended to the various tables which include more quantitative results. Accordingly, the boride layer thickness undergo a gradually increase with increasing temperature and holding time, which is consistent with the literature [12, 24]. In that, the thicknesses values of the boride layers vary from ∼18.70 μm to ∼152.43 μm, Table 3.…”

“…At a given holding time, the surface hardness values of the boride layers increase with increasing temperature, Table 3, Figure 3c. These results are consistent with those reported for hot working tool steel AISI H13 but do not correspond to those provided in a study conducted on HiTuf steel under the same temperature conditions for 5 h [12, 24]. Moreover, it can also be noted that at a given temperature and unlike the cases of surface thickness and roughness, there is no clear evidence that hardness increases with increasing holding time.…”

“…Boride layers tend to have a more or less smooth morphological appearance instead of the sawtooth morphology commonly found in low carbon steels [23]. This aspect can be ascribed to the high carbon content of the steel currently studied [24]. In this regard, it has been reported that tungsten and vanadium alloying elements (present in our steel) can transform the saw‐tooth morphology into boride surface with smooth interfaces [25].…”

“…It is only at a later stage that the boride layer (i. e., (Fe 9 B) 0.2 may form through the compound layer, Figure 5. This phase is reckoned to grow with the diffusing boron atoms from the surface toward the substrate in the direction of less resistance (i. e., the [001] crystallographic direction), the magnitude of which depend on the processing parameters, as well as the content of both carbon and alloying elements in the steel [24, 36]. In fact, when the carbon content is high, the size of the boride aciculae is brought to increase, while their extremities become rounded, Figure 6a.…”

Optimization of Cutting Parameters and Investigation of the Effect of Cutting Parameters on Hole Quality in Laser Drilling of Hardox 450 Steel

“…Ancak bu çeliklerin tribolojik performansı, oda sıcaklığında, aşındırıcı ortamlarda ve yüksek çalışma sıcaklıklar gibi bazı mühendislik uygulamalarda istenen performansı göstermede yetersiz kalabiliyor. Bu nedenle bu çeliklerin performansını artırmak için yüzeylerine farklı yöntemlerle kaplamalar uygulanmaktadır [1][2][3][4].…”