Sandvik Intellectual Property Ab

Sandvik Ab

Ulf Jutterström

Annika Kauppi

Alf Andersson

Bo Nelander

Stefan Backlund

The disclosure relates to a method for sorting a collection of bodies including cemented carbide bodies and non-cemented carbide bodies. A melt having one or more of bismuth, tin and lead and having a density in the range of 7.0-12.0 g/cmis provided. The collection is subjected to a sorting process based on density difference by providing the collection in the melt and allowing the bodies to be sorted into a first group at a top surface of the melt and a second group at a bottom of the melt. The first group includes non-cemented carbide bodies having a density lower than the density of the melt and the second group includes cemented carbide bodies having a density higher than the density of the melt. The present disclosure also relates to a method for recycling of cemented carbides comprising the sorting method and recycling of the second group.

Method for sorting a collection of bodies comprising cemented carbide bodies and non-cemented carbide bodies

A method for sorting hard metal including the steps of subjecting one or more bodies of hard metal to a heat treatment at a temperature of 500&#xb0; C. or higher in an atmosphere including at least one reactive gas component prone to form a reaction product with an element that may or may not be present in the one or more bodies. A sorting operation of the one or more bodies is performed based on a presence or absence of the reaction product in a surface portion of the heat treated one or more bodies.

Method for handling hard metal

The present invention relates to a method of making a ready-to-press agglomerated powder mixture by wet milling a powder mixture containing binder and spray drying said slurry to an agglomerated powder useful for making cutting tools for metal machining, tools for rock drilling and wear parts. If the binder is a baroplastic polymer having a pressure induced transformation from hard to soft well developed agglomerates with good flow properties and good plasticity are obtained. The hard property of the binder is used at normal pressures, during handling of the spray-dried powder and in the green body, whereas the softer properties are used at higher pressures during the pressing of the material when the pressure exceeds from about 10 to about 50 MPa.

Method of making cemented carbide or cermet agglomerated powder mixtures

The present invention relates to a method of making an agglomerated powder mixture by wet milling a powder mixture containing hard constituent powder(s) based on carbides of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo and/or W and greater than about 15 wt-% binder phase powder(s) of Co and/or Ni as well as pressing agents and spray drying said slurry. By adding to said powder mixture before milling in addition from about 0.05 to about 0.50 wt-% of a complex forming and/or pH-decreasing/increasing additive such as triethanolamine, hydroxides or acids and a thickener in an amount of from about 0.01 to about 0.10 wt-% agglomerates with excellent flow properties are obtained.

Method of making agglomerated cemented carbide powder mixtures

A new method and apparatus for manufacturing powders of cemented carbide, cermets, ceramics and similar materials with good abrasive wear resistance starting from a slurry, wherein the slurry is introduced into a drop forming device including at least one essentially horizontal oriented rotating drop forming disk (), from which the drops are slung out to solidify by centrifugal force. According to the invention the slurry is ejected from a discharge opening () on the drop former in the form of a jet such that it hits a first obliquely downward and inwardly directed surface () whereby the speed of rotation of the disk is chosen such that the jet of liquid is forced upwards over the first surface as well as over to another connected horizontal surface () and thereafter is ejected as a split jet against a second obliquely downwards-outwards directed surface () such that the slurry is accelerated to the speed of the drop forming disk () and then is led over a third surface () obliquely directed outwards, from where the drops are then caused to detach themselves and fall down, thus forming a powder.

Growing community of inventors

Stockholm, Sweden

Ulf Jutterström