Controlling ultra hard material quality

Abstract

A method is provided for controlling the consistency of the quality of ultra hard materials formed over tungsten carbide substrates formed from different batches of tungsten carbide powder by controlling the tungsten carbide particle size distribution in each batch.

1 . A method for controlling the quality of ultra hard material layers formed over a plurality of substrates formed from different batches of tungsten carbide powder, the method comprising: 
 selecting a first batch of tungsten carbide substrate powder material having a predefined particle size distribution;    selecting a second batch of tungsten carbide substrate powder material having a predefined particle size distribution, wherein the deviation between the particle size distribution of the first batch and the particle size distribution of the second batch is no greater than about 30%;    forming a first substrate from the first batch of powder substrate material;    forming a second substrate from the second batch of powder substrate material;    placing a first ultra hard material over the first substrate;    sintering the first ultra hard material with the first substrate forming a first ultra hard material layer over the first substrate;    placing a second ultra hard material over the second substrate; and    sintering the second ultra hard material with the second substrate forming a second ultra hard material layer over the second substrate, wherein a standard deviation of the strength of the two ultra hard material layers is not greater than 14%.    
     
     
         2 . The method as recited in  claim 1  wherein the strength of the first ultra hard material layer does not differ from the strength of the second ultra material layer by more than 10%.  
     
     
         3 . The method as recited in  claim 1  wherein the strength of the first ultra hard material layer does not differ from the strength of the second ultra material layer by more than 5%.  
     
     
         4 . The method as recited in  claim 1  wherein the hardness of the first substrate does not differ from the hardness of the second substrate by more than 2%.  
     
     
         5 . The method as recited in  claim 1  wherein the hardness of the first substrate does not differ from the hardness of the second substrate by more than 1%.  
     
     
         6 . The method as recited in  claim 1  wherein the magnetic saturation of the first substrate does not differ from the magnetic saturation of the second substrate by more than 15.4%.  
     
     
         7 . The method as recited in  claim 1  wherein the coercivity of the first substrate does not differ from the coercivity of the second substrate by more than about 43%.  
     
     
         8 . The method as recited in  claim 1  wherein the two substrates have a hardness within 1% of each other, a magnetic saturation within 15% of each other, and a coercivity within 43% of each other.  
     
     
         9 . The method as recited in  claim 1  wherein each substrate has a carbide particle mean size in the range of about 3 μm to 6 μm.  
     
     
         10 . The method as recited in  claim 9  wherein each substrate has a carbide particle mean size of about 3 μm and a maximum particle size of about 18 μm.  
     
     
         11 . The method as recited in  claim 1  wherein each substrate has a carbide particle mean size of about 4.5 μm to about 5.5 μm.  
     
     
         12 . The method as recited in  claim 1  further comprising: 
 selecting a third batch of tungsten carbide substrate powder material having a predefined particle size distribution, wherein the deviation between the particle size distribution of the first batch, the particle size distribution of the second batch, and the particle size distribution of the third batch is no greater than about 30%;    forming a third substrate from the third batch of powder substrate material;    placing a third ultra hard material over the third substrate;    sintering the third ultra hard material with the third substrate forming a third ultra hard material layer over the third substrate, wherein a standard deviation of the strength of the three ultra hard material layers is not greater than 14%.    
     
     
         13 . The method as recited in  claim 12  wherein the strength of each ultra hard material layer is within 10% of the strength of each of the other ultra hard material layers.  
     
     
         14 . The method as recited in  claim 12  wherein the strength of each ultra hard material layer is within 5% of the strength of each of the other ultra hard material layers.  
     
     
         15 . The method as recited in  claim 12  wherein the deviation between the three particle size distributions is not greater than about 20%.  
     
     
         16 . The method as recited in  claim 12  wherein the deviation between the three particle size distributions is not greater than about 10%.  
     
     
         17 . The method as recited in  claim 12  wherein the deviation between the two particle size distributions is not greater than about 5%.  
     
     
         18 . The method as recited in  claim 12  wherein each batch has 10% of its particles by volume having a size less than a first particle size, has 50% of its particles by volume having a size less than a second particle size, and has 90% of its particles by volume having a size less than a third particle size, wherein the deviation between the first particle sizes of the three batches is not greater than 5%, wherein the deviation between the second particles sizes of the three batches is not greater than 20% and wherein the deviation between the third particle sizes of the three batches is not greater than 30%.  
     
     
         19 . The method as recited in  claim 1  wherein the deviation between the two particle size distributions is not greater than about 20%.  
     
     
         20 . The method as recited in  claim 1  wherein the deviation between the two particle size distributions is not greater than about 10%.  
     
     
         21 . The method as recited in  claim 1  wherein the deviation between the two particle size distributions is not greater than about 5%.  
     
     
         22 . The method as recited in  claim 1  wherein each batch has 10% of its particles by volume having a size less than a first particle size, has 50% of its particles by volume having a size less than a second particle size, and has 90% of its particles by volume having a size less than a third particle size, wherein the deviation between the first particle sizes of the two batches is not greater than 5%, wherein the deviation between the second particles sizes of the two batches is not greater than 20% and wherein the deviation between the third particle sizes of the two batches is not greater than 30%.  
     
     
         23 . A method for controlling the quality ultra hard material layers formed over a plurality of substrates formed from different batches of tungsten carbide powder and cobalt, the method comprising: 
 forming a first ultra hard material over a first substrate formed from a first batch of tungsten carbide powder, wherein cobalt from the first substrate infiltrates said first ultra hard material via infiltration kinetics during said forming of said first ultra hard material layer;    forming a second ultra hard material over a second substrate formed from a second batch of tungsten carbide powder, wherein cobalt from the second substrate infiltrates said second ultra hard material via infiltration kinetics during said forming of said second ultra hard material layer;    controlling the infiltration kinetics of the cobalt in the first substrate; and    controlling the infiltration kinetics of the cobalt in the second substrate.    
     
     
         24 . The method as recited in  claim 23  wherein controlling the infiltration kinetics of the cobalt in the first substrate comprises controlling a first mean free path of the cobalt from the first substrate to the first ultra hard material layer and wherein controlling the infiltration kinetics of the cobalt in the second substrate comprises controlling a second mean free path of the cobalt from the second substrate to the second ultra hard material layer.  
     
     
         25 . The method as recited in  claim 24  wherein controlling the first mean path comprises selecting the first batch of tungsten carbide substrate powder material to have a predefined particle size distribution, and wherein controlling the second mean path comprises selecting the second batch of tungsten carbide substrate powder material to have a predefined particle size distribution, wherein the deviation between the particle size distribution of the first batch and the particle size distribution of the second batch is no greater than about 30%.  
     
     
         26 . The method as recited in  claim 25  wherein the deviation between the two particle size distributions is not greater than about 20%.  
     
     
         27 . The method as recited in  claim 25  wherein the deviation between the two particle size distributions is not greater than about 10%.  
     
     
         28 . The method as recited in  claim 25  wherein the deviation between the two particle size distributions is not greater than about 5%.  
     
     
         29 . The method as recited in  claim 25  wherein each batch has 10% of its particles by volume having a size less than a first particle size, has 50% of its particles by volume having a size less than a second particle size, and has 90% of its particles by volume having a size less than a third particle size, wherein the deviation between the first particle sizes of the two batches is not greater than 5%, wherein the deviation between the second particles sizes of the two batches is not greater than 20% and wherein the deviation between the third particle sizes of the two batches is not greater than 30%.  
     
     
         30 . A method for controlling the quality of ultra hard material layers formed over a plurality of substrates formed from different batches of tungsten carbide powder, the method comprising: 
 selecting a first batch of tungsten carbide powder material having a particle size distribution;    selecting a second batch of tungsten carbide substrate powder material having a particle size distribution, wherein the deviation between the particle size distribution of the first batch and the particle size distribution of the second batch is no greater than about 30%;    forming a first substrate from the first batch of material;    forming a second substrate from the second batch of material;    placing a first ultra hard layer material powder over the first substrate;    sintering the first ultra hard material with a first substrate forming a first ultra hard material layer over the first substrate;    placing a second ultra hard material over the second substrate; and    sintering the second ultra hard material with a second substrate forming a second ultra hard material layer over the second substrate.    
     
     
         31 . A method as recited in  claim 30  wherein the first batch has particle sizes in the range of 2 μm to 11.5 μm and a median particle size in the range of 4.5 μm to 5.5 μm.  
     
     
         32 . A method as recited in  claim 31  wherein the second batch has particle sizes in the range of 2 μm to 11.5 μm and a median particle size in the range of 4.5 μm to 5.5 μm.  
     
     
         33 . The method as recited in  claim 32  wherein each batch has 10% of its particles by volume having a size less than a first particle size, has 50% of its particles by volume having a size less than a second particle size, and has 90% of its particles by volume having a size less than a third particle size, wherein the deviation between the first particle sizes of the two batches is not greater than 5%, wherein the deviation between the second particles sizes of the two batches is not greater than 20% and wherein the deviation between the third particle sizes of the two batches is not greater than 30%.  
     
     
         34 . The method as recited in  claim 30  wherein each batch has 10% of its particles by volume having a size less than a first particle size, has 50% of its particles by volume having a size less than a second particle size, and has 90% of its particles by volume having a size less than a third particle size, wherein the deviation between the first particle sizes of the two batches is not greater than 5%, wherein the deviation between the second particles sizes of the two batches is not greater than 20% and wherein the deviation between the third particle sizes of the two batches is not greater than 30%.