Effect of Sulfur Content on the Composition of Inclusions and MnS Precipitation Behavior in Bearing Steel

MnS inclusions in bearing steel have long been considered to significantly affect the fatigue life of bearing steel. In this paper, the sizes of inclusions in bearing steel with different sulfur contents were analyzed and the precipitation behavior of MnS was calculated using thermodynamics. Furthermore, the positive role of MnS in bearing steel was discussed. Results showed that when the size of inclusions in bearing steel was increased, the proportion of MnS components in composite inclusions gradually decreased. When the sulfur content was increased, the shape of inclusions changed from a particle shape to a strip shape. With increasing MnS content, the inclusion ratio of Al2O3 was significantly reduced in the Al2O3–CaO–MgO–MnS quaternary inclusion system, particularly for MnS proportions greater than 20%. The content of sulfur in bearing steel significantly affects the precipitation temperature of MnS. When sulfur content increases from 0.001% to 0.007%, the precipitation temperature of MnS increases from 1493 K to 1633 K as the precipitation of MnS moves from the austenite solid phase to the liquid and solid phases, and the precipitation size of MnS inclusions significantly increases. The size of oxide inclusions should be controlled to improve MnS wrap oxide inclusions in steel. Based on these results, a composition control with high sulfur levels and low oxygen levels should be adopted to improve the fatigue performance of steel.

Download Full-text

Complex Precipitates of TiN-MCx in GCr15 Bearing Steel

10.20944/preprints201905.0289.v1 ◽

2019 ◽

Author(s):

Qianren Tian ◽

Guocheng Wang ◽

Xinghu Yuan ◽

Qi Wang ◽

Seetharaman Sridhar

Keyword(s):

Volume Fraction ◽

Early Stage ◽

Nucleation Site ◽

Bearing Steel ◽

Precipitation Behavior ◽

Heterogeneous Nucleation Site ◽

Bearing Steels ◽

Advancing Front ◽

Gcr15 Bearing Steel ◽

Second Phases

Nitride and carbide are the second phases which play an important role in the performance of bearing steel, and their precipitation behavior is complicated. In this study, TiN-MCx precipitations in GCr15 bearing steels were obtained by non-aqueous electrolysis, and their precipitation mechanisms were studied. TiN is the effective heterogeneous nucleation site for Fe7C3 and Fe3C, therefore, MCx can precipitate on the surface of TiN easily, its chemistry component consists of M3C and M7C3 (M = Fe, Cr, Mn) and Cr3C2. TiN-MCx with high TiN volume fraction, TiN forms in early stage of solidification, and MCx precipitates on TiN surface after TiN engulfed by the solidification advancing front. TiN-MCx with low TiN volume fraction, TiN and MCx form in late stage of solidification, TiN can not grow sufficiently and is covered by a large number of precipitated MCx particles.

Download Full-text

Analysis of precipitation behavior of MnS in sulfur-bearing steel system with finite-difference segregation model

Journal of Iron and Steel Research International ◽

10.1007/s42243-018-0117-0 ◽

2018 ◽

Vol 25 (8) ◽

pp. 803-812 ◽

Cited By ~ 3

Author(s):

De-lin Hu ◽

Hui Liu ◽

Jian-bo Xie ◽

Juan Cheng ◽

Jian Li ◽

...

Keyword(s):

Finite Difference ◽

Bearing Steel ◽

Precipitation Behavior

Download Full-text

Effect of low oxygen and high carbon dioxide atmospheres on the formation of volatiles during storage of two sweet cherry cultivars

Horticultural Science ◽

10.17221/165/2011-hortsci ◽

2012 ◽

Vol 39 (No. 4) ◽

pp. 172-180 ◽

Cited By ~ 5

Author(s):

J. Goliáš ◽

J. Létal ◽

O. Veselý

Keyword(s):

Carbon Dioxide ◽

Sweet Cherry ◽

Solid Phase ◽

Storage Period ◽

Total Volatile ◽

Low Oxygen ◽

Phenethyl Alcohol ◽

Hexenyl Acetate ◽

Sweet Cherry Cultivars ◽

Volatile Production

The aroma profiles of two sweet cherry cultivars Kordia and Vanda were investigated during storage at different oxygen and carbon dioxide levels and at a low temperature using solid phase microextraction gas chromatography combined with mass spectrometry (SPME-GC-MS). The most abundant aroma volatiles observed in both sweet cherry cultivars were alcohols, esters, terpenoids and aldehydes. Fifteen alcohols (but principally ethan-1-ol, (E)-2-hexen-1-ol and phenethyl alcohol) provided approximately 39% of the total volatile production and eight esters (principally (E)-2-hexenyl acetate and pentyl butyrate) were responsible for another 39% of the volatile production. Four terpenoids (principally limonene and α-linalool) were responsible for a further 15% of volatile production, and 10 aldehydes (principally (E)-2-hexenal and (E)-2-octen-1-al) were responsible for the remaining 7% of total volatile production. However, out of all the volatile compounds detected, a total of just 6 compounds (phenethyl alcohol, (E)-2-hexenal, (E)-2-octen-1-al, pentyl butyrate, (E)-2-hexenyl acetate and limonene) made up 80% of the total volatile production. Fruit stems remained green during all 54 days of the storage period, although one tenth of the stems slowly dessicated in each of the three controlled atmospheres. This is in marked contrast to the stems of fruit held in a regular atmosphere, which turned completely brown.  

Download Full-text

Segregation and Precipitation Behavior of Phosphorus in a Ni-Fe-Cr Base Wrought Superalloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.913.150 ◽

2018 ◽

Vol 913 ◽

pp. 150-156 ◽

Cited By ~ 1

Author(s):

Sha Zhang ◽

An Wen Zhang ◽

Wei Yang Wang ◽

Xin Xin ◽

Kai Zhang

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Grain Boundaries ◽

Energy Dispersive Spectroscopy ◽

Peak Temperature ◽

Energy Dispersive ◽

Precipitation Behavior ◽

Temperature Range ◽

Precipitation Temperature ◽

Scanning Electron

The segregation and precipitation behavior of phosphoruswas studied in aNi-Fe-Cr base wroughtsuperalloy. The precipitation behavior of phosphides in the alloy contained 0.025% Pwas examined after soaking at 750-1080°C to determine the precipitation temperature range of MNP-type phosphide. The microstructuresunder these various conditions wereinvestigated by scanning electron microscope(SEM) and energy dispersive spectroscopy (EDS). The precipitation temperature of the phosphide in the alloy was determined to be in the range of 850-1040 °C and the precipitation peak temperature was around 980°C.In addition, the melting temperatureof the phosphide was determined to be between 1200 °C and 1250 °C. The current results indicate the tendency of phosphorus segregated at grain boundaries.

Download Full-text

Quality control of epitaxial LiCoO2 thin films grown by pulsed laser deposition

Journal of Materials Research ◽

10.1557/jmr.2010.0250 ◽

2010 ◽

Vol 25 (10) ◽

pp. 1886-1889 ◽

Cited By ~ 35

Author(s):

T. Ohnishi ◽

B.T. Hang ◽

X. Xu ◽

M. Osada ◽

K. Takada

Keyword(s):

Thin Films ◽

Pulsed Laser Deposition ◽

Pulsed Laser ◽

Growth Parameter ◽

Laser Deposition ◽

Low Oxygen ◽

High Quality ◽

Composition Control ◽

Ablation Laser ◽

Lower Valence

Thin films of c-axis-oriented LiCoO2 were epitaxially grown by pulsed laser deposition (PLD). The ablation laser conditions greatly affect the crystal quality of the epitaxial LiCoO2 thin films. In addition, high-quality LiCoO2 thin films were found to grow without any impurity phases under relatively low oxygen partial pressure, although high pressure had been often selected to suppress the formation of Co3O4 with a lower valence state as an impurity. This result clearly indicates that the ablation laser conditions are an essential growth parameter, and that composition control is indispensable to grow high-quality complex compound thin films by PLD.

Download Full-text

Effects of Ti/Mo and Ti/Cu ratio on precipitation behavior of Ti-bearing steel: findings from experiments and critical patent analysis

Journal of Materials Research and Technology ◽

10.1016/j.jmrt.2021.08.148 ◽

2021 ◽

Vol 15 ◽

pp. 1430-1445

Author(s):

Chih-Yuan Chen ◽

Ya-Hui Lin ◽

Po-Han Chiu ◽

Zhen-Wei Chen ◽

Wen-Shan Liu

Keyword(s):

Bearing Steel ◽

Patent Analysis ◽

Precipitation Behavior

Download Full-text

Precipitation behavior of titanium nitride on a primary inclusion particle during solidification of bearing steel

Journal of Iron and Steel Research International ◽

10.1016/s1006-706x(17)30103-6 ◽

2017 ◽

Vol 24 (7) ◽

pp. 685-690 ◽

Cited By ~ 4

Author(s):

Liang Yang ◽

Bryan A. Webler ◽

Guo-guang Cheng

Keyword(s):

Titanium Nitride ◽

Bearing Steel ◽

Inclusion Particle ◽

Precipitation Behavior ◽

Primary Inclusion

Download Full-text

The Reactivity of Polyethylene Microplastics in Water under Low Oxygen Conditions Using Radiation Chemistry

Water ◽

10.3390/w13213120 ◽

2021 ◽

Vol 13 (21) ◽

pp. 3120

Author(s):

Julie R. Peller ◽

Stephen P. Mezyk ◽

Sarah Shidler ◽

Joe Castleman ◽

Scott Kaiser ◽

...

Keyword(s):

Surface Characterization ◽

Solid Phase ◽

Degradation Products ◽

Morphological Changes ◽

Aqueous Solubility ◽

Radiation Chemistry ◽

Dark Field ◽

Gas Chromatography Mass Spectrometry ◽

Low Oxygen ◽

Oxygen Conditions

Polyethylene (PE) is an intensely utilized polymer, which has consequently led to it becoming a common environmental contaminant. PE and other plastic waste are known to be highly persistent in surface waters; however, chemical and physical changes do take place over time, dependent mostly on highly variable natural conditions, such as oxygen (O2) availability. Gamma radiation was used to generate reactive oxygen species, namely hydroxyl radicals, in initially aerated aqueous solutions to simulate the natural weathering of microplastics in waters where there are fluctuations and often depletions in dissolved O2. The headspace of the irradiated PE-containing solutions was probed for the formation of degradation products using solid-phase microextraction (SPME) fibers in combination with gas chromatography mass spectrometry (GCMS). The major species detected were n-dodecane, with trace levels of tridecane, 2-dodecanone, and hexadecane, which were believed to be predominately adsorbed in the PE microplastics in excess of their aqueous solubility limits. Surface characterization by Raman spectroscopy and light and dark field microscopy indicated no change in the chemical composition of the irradiated PE microplastics under low O2 to anaerobic conditions. However, morphological changes were observed, indicating radical combination reactions.

Download Full-text

Precipitation and Precipitation Hardening Behavior of V and/or Cu Bearing Middle Carbon Steels

Materials Science Forum ◽

10.4028/www.scientific.net/msf.638-642.3491 ◽

2010 ◽

Vol 638-642 ◽

pp. 3491-3495 ◽

Cited By ~ 2

Author(s):

Takehide Senuma ◽

Masanori Sakamoto ◽

Yoshito Takemoto

Keyword(s):

Carbon Steel ◽

Precipitation Hardening ◽

Bearing Steel ◽

Carbon Steels ◽

Precipitation Behavior ◽

Hardening Behavior ◽

Precipitation Treatment ◽

Interphase Precipitation

In this study, the precipitation and precipitation hardening behavior of a 0.3%V and 2%Cu bearing middle carbon steel has been investigated in comparison with that of a 0.3%V bearing steel and a 2%Cu bearing steel. The precipitation treatment was carried out isothermally at 600°C.The amount of the precipitation hardening of the 0.3%V and 2%Cu bearing steel is nearly equal to the sum of the precipitation hardening of the 0.3%V bearing steel and the 2%Cu bearing steel In the 0.3%V bearing steel, precipitates were observed in rows, which indicates the occurrence of the interphase precipitation while precipitates observed in the 2%Cu bearing steel were randomly dispersed. In the V and Cu bearing steel, randomly dispersed precipitates were not observed where there were aligned precipitates. In the paper, the different precipitation behavior of the three steels is discussed.

Download Full-text