Flexural strength, also known as Transverse Rupture Strength (TRS), is a primary mechanical property used to evaluate the structural integrity of cemented carbide.
At Langsun Carbide, TRS testing confirms that each tungsten carbide grade provides the required resistance to bending and fracture under real operating loads.
Three-Point Bending Test Procedure
We measure flexural strength using the three-point bending method, which is widely applied to cemented carbide:
1.Specimen Preparation
Standard test bars are pressed and sintered together with the production batch. After sintering, the bars are ground to the specified dimensions and edge condition.
2.Test Setup
The specimen is placed on two supports with a fixed span. A loading nose applies an increasing force at the midpoint until the specimen fractures.
3.TRS Calculation
Transverse Rupture Strength (TRS) is calculated using the maximum load at fracture, the support span, and the specimen dimensions.
Multiple specimens are tested per batch to obtain statistically representative results.
Why Flexural Strength Is Important
Tungsten carbide is extremely hard but relatively brittle. For routine quality control, a bending test is often more appropriate than a tensile test:
● More Representative of Real Loads — Many components experience bending and combined stresses during service.
● More Sensitive to Defects — Porosity, cracks, coarse grains, and binder segregation can all reduce flexural strength.
● Directly Linked to Reliability — Higher and more consistent TRS values indicate better resistance to chipping and catastrophic fracture.
For applications such as oil & gas nozzles, mining wear parts, cutting tools, and valve internals, sufficient flexural strength is critical to prevent unexpected failures.
Flexural Strength Control at Langsun Carbide
● Grade-Specific TRS Targets — Each tungsten carbide grade has a minimum flexural strength (TRS) requirement matched to its intended application and hardness level.
● Correlation with Microstructure — TRS results are reviewed alongside metallography, density, and hardness to diagnose potential structural issues.
● Used in Grade Development — When developing tougher grades or optimizing the sintering process, we rely on TRS testing to quantify improvements.
● Customer Documentation — Flexural strength values can be included in datasheets and certification reports to support customer design calculations and safety evaluations.
Through systematic flexural strength testing, Langsun Carbide delivers tungsten carbide products that combine high wear resistance with reliable mechanical integrity.
Indicative TRS Ranges for Representative Grades
The table below shows indicative transverse rupture strength ranges for representative WC–Co grades. Exact values depend on detailed composition and processing and are defined in grade specifications.
|
Grade |
wCo/% |
Typical TRS Range (MPa) |
Typical Hardness Level |
Typical Applications |
|
WC-6Co |
6 |
2000 – 2600 |
High hardness |
Nozzles, wear plates, high-load seal faces |
|
WC-11.5Co |
11.5 |
2200 – 2800 |
Balanced hardness & toughness |
General wear parts, bushings, sleeves, valve components |
|
WC-15Co |
15 |
2400 – 3000 |
Higher toughness |
Impact-prone tools, heavy-duty mining and drilling components |
Note: TRS values are indicative reference ranges.