WMT&R has established a
world-renowned reputation for dependable Fracture Toughness Testing. Our
state-of-the-art Fracture Lab is designed for the high volume quick turn
around projects demanded by the Aerospace, Power Generation, Petroleum, Nuclear, and
Fracture Toughness Tests are
generally performed on specimens containing a flaw and this requires an operation, called precracking, to induce a flaw
of a specific specification. Precracking can be performed on any of WMT&R's
240+ servo machines, which
cover a range of load capacities up to a 1,000,000-lb. fatigue load. The
actual crack, which initiates at the top of a machined notch, is generally
measured using various automatic techniques including EPD and Compliance.
Tests are performed at temperatures ranging from Liquid Helium to over
2000°F under various controlled conditions or atmospheres including salt
water, argon, vacuum, and high humidity.
Here at WMT&R's Fracture Toughness & Fatigue Testing
Laboratory we most often perform the KIC Test per ASTM E-399 which includes disc shape, arc tension, arc bend, single-edge
bend, and compact tension. Regarding compact tension testing, we are
equipped to perform tests on sizes ranging from .25" thick up to 4.25" thick
for most applications. We have also machined and tested steel compact
tension specimens up to 8" thick weighing 1000 lbs.
Additional fracture based services include JIC, KIE - Surface Crack Tension, KR, R Curve, KIV - Short Rod and
Short Bar, K-EE - Equivalent Energy, CTOD - Crack Tip Opening Displacement; KISCC and K-Salt Stress Corrosion.
WMT&R conducts KR, R-Curve testing
to ASTM E-561 on both compact specimens C(T) and center-cracked tension
panels M(T). We have the unique ability to test large M(T) panels at
cryogenic temperatures. The KR, R-Curve test provides valuable data about
the toughness development as a crack is stably propagated under an
increasing intensity factor K. R-Curves and applied K Curves are used to
predict the critical stress intensity that will cause the onset of unstable
Chevron Notch Short
Rod/Short Bar is another type of Fracture Toughness specimen with
which we have extensive machining and testing experience. WMT&R has the machining and
testing expertise to handle a wide range of specimen sizes from 0.25 inches
to 2.0 inches in the B dimension. The fracture toughness determined by this
test shows the resistance of a material to fracture from gradually advancing
steady state crack, utilizing a severe tensile constraint, in a neutral
environment. A KIV, KIVJ or KIVM value may be assigned to estimate the
correlation of failure stress and defect size.
(SCT) testing is conducted to ASTM E-740 and is relied upon to estimate the
load-carry ability of sheet or plate components with a flaw that could
possibly occur during actual use. Our fracture toughness department
routinely conducts this test to cryogenic temperatures down to -450°F.
Research uses for this test include studying failure characteristics of
cracks under simulated service conditions.
In addition to fracture
mechanics based testing this department also specializes in conducting
various other types of test including peel test, flexure, shear (single,
double, slotted or LAP) and rising load testing to name a few.
Reports are automatically
generated using our innovative database system, which can be transferred
directly and securely to your database via an Electronic Data Interface
Our Fracture Toughness Testing Capabilities include:
Proprietary state of the art software and
unrivaled facilities for performing:
Nil Ductility Transition Temperature,
Dynamic Tear Testing,
Notched Bar Impact (Charpy and Izod),
Facilities for Testing from -423°F to +2100°F
Machine Shop specializing in Specimen Preparation
Our subsidiary in the UK, WMT&R, Ltd., offers
an impressive array of Fracture
Toughness Tests to meet your needs.