Simulating Fatigue Cracks Growth in Spiral Bevel Gears Part 6 pptx

... [ksi *in °'5] Figure 4.7: Intrinsic fatigue crack growth rate for AISI 9310 in 250 ° oil; I¢ = 1. Table 4.2: Intrinsic and non-intrinsic fatigue crack growth rate parameters. C C* Test n [ (in/ cycle)/(ksi,ino.5).] ... 5.748 daJdN (in cycle 10 .7) 0.153 0. 160 0.549 0. 561 1.1 36 1.1 46 1.1449 1.451 1 .63 7 1 .63 9 1.841 1.844 2.303 2.3 06 2.841 2.844 % Change x daldN 4....

Ngày tải lên: 11/08/2014, 20:21

... front is now NASAJCR 2000-210 062 2 NASA / CRm2000-210 062 Simulating Fatigue Crack Growth in Spiral Bevel Gears Lisa E. Spievak, Paul A. Wawrzynek, and Anthony R. Ingraffea Cornell University, ... tremendous increase in computing power. Section 1.2 summarizes recent research related to modeling gears numerically. Limited work has focused on predicting crack trajectories in...

Ngày tải lên: 11/08/2014, 20:21

... die of spiral bevel gears. The progression of research related to computer analysis of gears has led to the investigation of crack growth in spiral bevel gears. FEM models of spiral bevel gears can ... mating gears are mounted are a few of the distinguishing characteristics between the gear types. Gears with intersecting shafts are called bevel gears. The most co...

Ngày tải lên: 11/08/2014, 20:21

... a variety of failures from tooth bending fatigue to spalling to rolling contact fatigue in both spur and spiral bevel gears, The effective case depth is defined as the depth to reach 50 RC. x[Coy ... determine gear stresses and life. 2 .6 Chapter Summary This chapter covered basic terminology and geometry aspects of gears. Concepts related to spiral bevel gears were the p...

Ngày tải lên: 11/08/2014, 20:21

... l, log(_l) ntrinsic Ul'Ve Figure 3.5: Schematic of fatigue crack growth rate data in Paris regime at different stress ratios collapsing into a single "intrinsic" curve. Using Paris' ... focus on crack growth in regime II. Crack initiationl smallcrack effects, and unstable Crack growth (regime III) Will be ignored. A seminal development in predicting fatigue...

Ngày tải lên: 11/08/2014, 20:21

... scatter in fatigue crack growth rates at different stress ratios in AISI 9310 steel. Table 4.2 contains the slopes and vertical intercepts from the lines in the figures. In addition, a linear least ... Utilized in the work Of chapters 4, 5, and 6. The studies in those chapters cover issues related to predicting three dimensional fatigue crack trajectories in a spiral b...

Ngày tải lên: 11/08/2014, 20:21

... displacements, and likewise SIFs, in the tooth root will thus increase. 18000 160 00 14000 12000 :_ 10000 _. _2 8ooo 60 00 4000 2000 1 6 11 16 21 26 31 36 41 46 51 56 61 Crack front position (Orientation: ... also indicates which loading mode is driving the crack growth. Mode I dominant fatigue crack growth is associated with smaller ratios. Qian et al. [ 19 96] studied mixed...

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... pictures. NASA/CR 2000-210 062 78 CHAPTER SEVEN: DISCUSSION AND SENSITIVITY STUDIES 7.1 Introduction In Chapter 5, fatigue crack growth in the OH-58 spiral bevel pinion under moving, non-proportional ... some texture combined with flattened areas was observed further from the notch near the ridge (point C in Figures 6. 3 and 6. 4). In Figures 6. 3 and 6. 4, this combinatio...

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... parameters. da/dN l° [in/ cycle] 9.30e -6 2.03e -6 Cycles /inch I Fatigue Life 1 107,527 67 5,838 492 ,61 1 3,0 96, 201 64 ,935 81,301 408,145 511,000 The fatigue life estimates using each set of parameters in Table ... surfaceshowingassumedshapeof largecrack(dashedline). A few cyclesof crack growth arecarriedout using the methoddescribedin Section 3.2.3. Thismethod assumesmodeI...

Ngày tải lên: 11/08/2014, 20:21

... is concludedthatthemovingloadmethod'strajectoriesaremoreaccurate. In summary,insightsinto the intricaciesof modelingfatiguecrack growth in threedimensionsweregained. Preliminary stepstoward accuratelymodelingcrack growth ... trajectories in a spiral bevel pinion required expanding the state-of-the-art capabilities and theories for predicting fatigue crack growth rates a...

Ngày tải lên: 11/08/2014, 20:21