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Fatigue is a structural failure mode that must be recognized and understood to develop products that meet life cycle durability requirements. In the age of lightweighting, fatigue strength is an important vehicle design requirement as engineers struggle to meet stringent weight constraints without adversely impacting durability. This technical concept course introduces the fatigue failure mode and analysis methods. It explains the physics of material fatigue, including damage accumulation that may progress to product failure over time, and it provides the needed foundation to develop effective fatigue prediction capabilities.

Parts, such as bolts, turbine wheels, discs, buckets, and blades, for high strength and oxidation resistance up to 1500 F when suitably heat treated.

This specification covers all-metal, self-locking nuts, plate nuts, and gang channel nuts made of a carbon or low-alloy steel.

This specification covers all-metal, self-locking, prevailing-torque nuts, plate nuts, and gang channel nuts made of a carbon or low-alloy steel.

A combination of laboratory reactor measurements and vehicle FTP testing has been combined to demonstrate a method for diagnosing the formation of NO2 from a diesel oxidation catalyst (DOC). Using small cores from a production DOC and simulated diesel exhaust, the laboratory reactor experiments are used to support a model for DOC chemical reaction kinetics. The model we propose shows that the ability to produce NO2 is chemically linked to the ability of the catalyst to oxidize hydrocarbon (HC). For thermally damaged DOCs, loss of the HC oxidation function is simultaneous with loss of the NO2 production function. Since HC oxidation is the source of heat generated in the DOC under regeneration conditions, we conclude that a diagnostic of the DOC exotherm is able to detect the failure of the DOC to produce NO2. Vehicle emissions data from a 6.6 L Duramax HD pick-up with DOC of various levels of thermal degradation is provided to support the diagnostic concept.

As a result of recommendation from the Augustine Panel, the direction for Human Space Flight has been altered from the original plan referred to as Constellation. NASA's Human Exploration Framework Team (HEFT) proposes the use of a Shuttle Derived Heavy Lift Launch Vehicle (SDLV) and an Orion derived spacecraft (salvaged from Constellation) to support a new flexible direction for space exploration. The SDLV must be developed within an environment of a constrained budget and a preferred fast development schedule. Thus, it has been proposed to utilize existing assets from the Shuttle Program to speed development at a lower cost. These existing assets should not only include structures such as external tanks or solid rockets, but also the Flight Software which has traditionally been a ?long pole? in new development efforts. The avionics and software for the Space Shuttle was primarily developed in the 70's and considered state of the art for that time.

Can you become a visionary or are you born one? How does a visionary capture an opportunity and makes it a successful business? Are engineers more qualified to solve technical problems or run companies? SAE's "The Visionary's Take" addresses these and many other questions, by talking directly with those who have dared to tackle difficult engineering problems, and create real-life products out of their experience. In these short episodes, Sanjiv Singh and Lyle Chamberlain, respectively CEO and Chief Engineer from Near Earth Autonomy, talk about their experience in creating a brand-new company in the UAV world. Founded in 2011, Near Earth Autonomy brought together a group of engineers and roboticists, looking for unconventional solutions to very hard logistics problems, presenting danger to human life. The answers were developed by pushing technology to a higher level, testing quickly and often, and keeping an open mind to alternative ways of framing engineering challenges.

Can you become a visionary or are you born one? How does a visionary capture an opportunity and makes it a successful business? Are engineers more qualified to solve technical problems or run companies? SAE's "The Visionary's Take" addresses these and many other questions, by talking directly with those who have dared to tackle difficult engineering problems, and create real-life products out of their experience. In these short episodes, Sanjiv Singh and Lyle Chamberlain, respectively CEO and Chief Engineer from Near Earth Autonomy, talk about their experience in creating a brand-new company in the UAV world. Founded in 2011, Near Earth Autonomy brought together a group of engineers and roboticists, looking for unconventional solutions to very hard logistics problems, presenting danger to human life. The answers were developed by pushing technology to a higher level, testing quickly and often, and keeping an open mind to alternative ways of framing engineering challenges.

We're working to solve the STEM crisis and building the next generation of engineers and scientists with our Kindergarten-College programs supported by the SAE Foundation: - A World In Motion (AWIM) Kindergarten-8 - Collegiate Design Series (CDS) College Help us inspire curiosity in STEM: find out more at saefoundation.org today.

Micro-pitting is a fatigue effect that occurs in geared transmission systems due to high contact stress, and monitoring its progression is vital to prevent the eventual failure of the tooth flank. Parameter signature analysis has been successfully used to monitor bending fatigue failure and advanced phases of gear surface fatigue failure such as macro-pitting and scuffing. However, due to modern improvements in steel production the main cause of gear contact fatigue failure can be attributed to surface micro-pitting rather than sub-surface phenomena. Responding to the consequent demand to detect and monitor the progression of micro-pitting, this study experimentally evaluated the development of micro-pitting in spur gears using vibration and oil debris analysis. The paper presents the development of an online health monitoring system for use with back-to-back gear test rigs.

Composite bearings of PTFE as the base material have been widely used for automotive parts. However, in recent years, due to downsizing, faster sliding speeds, and tendency to increase the bearing load with high performance, particularly for boundary lubrication conditions, the PTFE-based composite bearing is often worn, making it difficult to apply to some applications. A high strength polymer was selected as an alternative to PTFE base material, and the mechanical properties and performance in a start-stop test, reciprocating sliding test and seizure test were evaluated. Focusing on the characteristics of high strength, by applying a PEEK resin, in each evaluation, it was confirmed that superior performance was achieved compared with a conventional PTFE based composite bearing. Presenter Yohei Takada, Daido Metal Co., Ltd.

The development of PM and NOx reduction system with the combination of DOC included DPF and SCR catalyst in addition to the AOC sub-assembly for NH3 slip protection is described. DPF regeneration strategy and manual regeneration functionality are introduced with using ITH, HCI device on the EUI based EGR, VGT 12.3L diesel engine at the CVS full dilution tunnel test bench. With this system, PM and NOx emission regulation for JPNL was satisfied and DPF regeneration process under steady state condition and transient condition (JE05 mode) were successfully fulfilled. Manual regeneration process was also confirmed and HCI control strategy was validated against the heat loss during transient regeneration mode. Presenter Seung-il Moon