摘要 |
<p>A servo controlled test arrangement (15) for testing specimen (18) has both load and stroke control inputs that are coupled together with a gate (164) to permit tensile testing a specimen (18) while controlling the load on the specimen (18), and when the specimen yields, for safely and smoothly switching to stroke control to complete the test and break the specimen (18). Control over the velocity of the actuator is provided as the specimen (18) yields, and to prevent the specimen (18) from being placed into compression, and also to sense the specimen plastic deformation after it has yielded a desired amount, but before the stroke control function is activated.</p> |