Air bag bike helmet

Stanford University, Calif., bioengineer David Camarillo tested a new type of bike helmet that comes in a soft pocket worn around the neck.

One Minute Mentor: Hardening Martensitic Stainless Steels

Certain anomalies in these steels that should be considered before specifying a heat-treating procedure are exemplified in the opposing injurious effects of the high and low extremes of austenitizing temperature, depending on the subsequent tempering temperature.