Simulating Fatigue Cracks Growth in Spiral Bevel Gears Part 3 pot

... 0.15 3. 00 1.00 0.08 95 .30 = Maximum 0. 13 0.70 0.015 0.015 0 .35 0 .35 3. 50 1.40 0.001 0.15 93. 39 Most gears are case hardened. Case hardening increases the wear life of the gear. In general, the gears ... Modulus Poisson's Ratio Fracture Toughness 3 Average Grain Size 4 c)perties of AISI 931 0. 185 x 10 3 psi 160 x 10 3 psi 30 x 106 psi 0 .3 85 ksi *in °5 ASTM No....

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' ... from the initial length in Figure 3. 8 to that in Figure 3. 9 is 4,900 cycles. 3. 2 .3 Example: Three dimensional, mode I dominant fatigue crack growth simulation with s...

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... Slope and intercept of curves in Figures 4.4 and 4.5. Test n R=-I (Air) 3. 3 R = 0.05 (Air) 3. 5 R = 0.5 (Air) 3. 9 C [ (in/ cycle)/(ksi* in 5) n] 6.4e-12 7.3e- 11 5.3e-11 R = -1 (Oil) 3. 2 1.1e-11 R ... scatter in fatigue crack growth rates at different stress ratios in AISI 931 0 steel. Table 4.2 contains the slopes and vertical intercepts from the lines in the figures. I...

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... results in a constant kink angle for the load cycle. Since the ratio is changing in the spiral- bevel gear tooth, the predicted angle of propagation during the load cycle changes. A method to determine ... also indicates which loading mode is driving the crack growth. Mode I dominant fatigue crack growth is associated with smaller ratios. Qian et al. [ 1996] studied mixed mode I a...

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... reporting burden for this collection of information Is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining ... Washington, DC 205 03. 1. AGENCY USE ONLY (Leave blank) 2. REPORT DATE 3. REPORT TYPE AND DATES COVERED May 2000 Final Contractor Report 4. TITLE AND SUBTITLE Simulating Fatigue Crac...

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... proportional loading 31 3. 3 Fracture Mechanics Software 33 3. 4 Chapter Summary 34 CHAPTER FOUR: FATIGUE CRACK GROWTH RATES 35 4.1 4.2 4 .3 4.4 4.6 Introduction 35 Fatigue Crack Closure Concept 35 Application ... LABORATORY Simulating Fatigue Crack Growth in Spiral Bevel Gears Lisa E. Spievak, Paul A. Wawrzynek, and Anthony R. Ingraffea Cornell University, Ith...

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... 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...

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... [ksi *in °'5] Figure 4.7: Intrinsic fatigue crack growth rate for AISI 931 0 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).] ... [ (in/ cycle)/(ksi,ino.5).] [ (in/ cycle)/(ksi,inO :).] R = -1 (Air) 3. 3 6.4e-12 6 .30 e-10 R = 0.05 (Air) 3. 5 7.3e-11 8.80e-10 R = 0.5 (Air) 3. 9 5.3e-11...

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... STUDIES 7.1 Introduction In Chapter 5, fatigue crack growth in the OH-58 spiral bevel pinion under moving, non-proportional loads was predicted. Chapter 6 presented experimental fatigue crack ... presenting data from an OH-58 spiral bevel pinion test. The test was conducted by NASA/GRC. EDM notches were introduced into the root of nine of the pinion teeth to serve as starter...

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... taken from a curve fit to the intrinsic fatigue crack growth rate data (no closure) for AISI 931 0 tested in 250 ° oil. These values were 3. 36 and 6.19e-20 (in/ cycle)/(psi *in 5) ", respectively. ... to an intrinsic fatigue crack growth rate curve. Table 7.1: Source n Forman et al. 1. 63 _ [19841 Au et al. [1981]11 2.56 Air test 3. 63 [Proprietary 1998] Oil test [Proprie...

Ngày tải lên: 11/08/2014, 20:21