A wear resistance plate combining nodular iron and cemented carbides is said to offer  unprecedented resistance to both impact and abrasion, extending the wear life of mining equipment.

Sandvik Rock Processing’s HX900 wear protection plates are used in applications such as feeders, feed chutes, transfer chutes, skirt liners, rock box edge liners, load-haul equipment and buckets and have been deployed mainly in countries including Australia, Brazil, Peru, Sweden and the US. Having demonstrated results in real life mining applications, the plates are now being launched in Africa.

“What makes our HX900 wear protection plate so effective is the unique combination of two different mechanical properties in a single piece,” says Sandvik Rock Processing regional manager: screening media and wear protection Africa Phumi Motsamai. “The nodular iron resists the high impact of material, while the cemented carbides provide outstanding resistance to abrasion.”

Motsamai explains that carbide has been shown to last up to five times longer than white iron, and up to 20 times longer than quenched steel. The longer wear life means extended replacement intervals and lower total cost of ownership. This brings a range of operational benefits including higher productivity through less downtime, and improved safety as maintenance technicians are less frequently in contact with equipment. There is also less need for high volumes of replacement inventory to be stored on site.

The nodular iron, also known as ductile iron, is a special type of cast iron with a characteristic microstructure that enhances its mechanical properties. It contains graphite in the form of nodules or spheroids, which impart ductility and toughness.

“Nodular iron has a higher tensile strength and can undergo significant deformation without failing,” says Motsamai. “It absorbs energy well and has good fatigue resistance, making it ideal for components that are subject to dynamic and cyclic loading conditions.”

The cemented carbides in HX900 consist of hard carbide particles bonded together by a metallic binder of primarily tungsten carbide. With a hardness of about nine on the Mohs scale, tungsten carbide is one of the hardest known materials, just behind diamonds and cubic boron nitride.

“Compared to quenched and tempered 500 HB steels, cast-in-carbides can last up to 10 times longer. This improvement can be up to 50 times longer compared to regular chromium carbide overlays and white iron,” notes Motsamai.

This innovation also has important sustainability benefits for customers, she continues, as the carbide production makes a key contribution to the circular economy.

“Our HX900 plates embody high levels of good sustainability practice, as they utilise 99% recycled nodular iron and 100% recycled cemented carbides,” she says. “Research has shown that using recycled materials in this way consumes 70% less energy and cuts overall CO2 emissions by 40%.”