Ring Crack Initiation Load of Silicon Nitride Bearing Balls

Ichikawa, Masahiro; Takamatsu, Tohru; Shindou, Naoki; Okabe, Nagatoshi; Abe, Yutaka

doi:10.1299/jsmea1993.38.2_226

Cited by 4 publications

(2 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…S ilicon nitride (Si 3 N 4 ) balls for use in hybrid bearings have been shown to extend rolling contact fatigue (RCF) lifetime, reduce the dynamic loading in high‐speed roller element applications because of their lower density compared with steel balls, and enable bearing use in more corrosive and higher temperature environments 1–3 . During their development, many parameters such as density, hardness, elastic modulus, fracture toughness, three‐ and four‐point flexure strength and Weibull modulus, crushing strength, grain size and secondary phase morphology, porosity, and surface finish have been extensively studied in an effort to improve or predict the RCF performance of Si 3 N 4 balls 1–7 . As an outcome of many of these studies, ASTM F2094 8 was developed to specify allowable minima and maxima of many of those properties and finish conditions.…”

Section: Introductionmentioning

confidence: 99%

Strength Measurement of Ceramic Spheres Using a Diametrally Compressed “C‐Sphere” Specimen

Wereszczak

Kirkland

Jadaan

2007

Journal of the American Ceramic Society

View full text Add to dashboard Cite

A ''C-sphere'' specimen geometry was conceived and developed to measure failure stress of bearing-grade silicon nitride (Si 3 N 4 ) balls caused by tension at the ball's surface. The induced method of fracture also allows for the study of surface-located strengthlimiting flaws in ceramic spheres. A slot is machined into the balls to a set depth to produce the C-sphere geometry. A simple, monotonically increasing uniaxial compressive force produces an increasing tensile stress at the C sphere's outer surface that ultimately initiates fracture. The strength is determined using a combination of failure load, C-sphere geometry, and finite element analysis. Additionally, the stress field was used to determine the effective areas and effective volumes of a C-sphere as a function of Weibull modulus. To demonstrate this new specimen, C-sphere flexure strength distributions were determined for three commercially available bearing-grade Si 3 N 4 materials (NBD200, SN101C, and TSN-03NH), and differences among their characteristic strengths and Weibull moduli were found.

show abstract

Section: Introductionmentioning

confidence: 99%

Strength Measurement of Ceramic Spheres Using a Diametrally Compressed “C‐Sphere” Specimen

Wereszczak

Kirkland

Jadaan

2007

Journal of the American Ceramic Society

View full text Add to dashboard Cite

show abstract

“…This has been attributed to the small volume acted upon by the contact-induced tensile stress. Ring crack initiation load of HIP Si 3 N 4 bearing balls was experimentally studied by some researchers [6][7]. Initiation of a ring crack was detected using acoustic emission.…”

Section: Surface Crack Defectsmentioning

confidence: 99%