Fractured presintered zirconia

[CAM_R&D]

The primary reason for using isostatic pressing is uniformity of density, and therefore uniformity of shrinkage across the full volume of the blank. With axial pressed discs, the central section will always be denser than the outer perimeter. It is very possible to produce much denser discs with axial pressing than with iso, should that be required, but what is much more important is the uniformity which can not be achieved by axial pressing. Your bridges will not be as accurate if axial pressed blanks are used. Strength is not the issue here.

 

[grantoz]

what are you using to cut it out.we use shape carbide high speed cuts like butter no vibration. about 8 years ago we had a bad batch of zirk and it broke every time .when you mount it in the machine tap it with your finger if you hear vibration its problem time.

 

[Pieter]

If i am right informed wieland,aman girrbach and zirkonzahns tranlucent zirkons are only biaxial pressed and ag has one of the best technical data.

Reckon you are misinformed about all 3

 

[cadfan]

Reckon you are misinformed about all 3

Enrico told me in a training zz pretau is biaxial pressed

wieland see below uniaxial the two press stamp can be individually controlled so its called uniaxial by two stamps ???

in the older days i thought if seen a datasheet about zolid ( 100 tonns biaxial) cant find it anymore the secret behind the zirkon as my zirkon manufakturer said 90 % bull........it

You can give us clear info if you know it better pieter

 

[ayane]

The primary reason for using isostatic pressing is uniformity of density, and therefore uniformity of shrinkage across the full volume of the blank. With axial pressed discs, the central section will always be denser than the outer perimeter. It is very possible to produce much denser discs with axial pressing than with iso, should that be required, but what is much more important is the uniformity which can not be achieved by axial pressing. Your bridges will not be as accurate if axial pressed blanks are used. Strength is not the issue here.

Good info in this thread.

From the picture above is uniaxially pressing. nothing against this process as it is used by many manufacturers. IT will work for single units, but you start with bridges and you will have a very noticable distortion.

Isostatic pressing will ensure density uniformity which ensure uniformity of shrinkage and therefor uniformity of fit.

 

[cadfan]

We dont talk about the past we talk about now and here and the new !!! translucent zirkon in the past everybody was proud to show on the website isostatic pressed or maybe up to 14 mm biaxial or uniaxial look now if you find information about that by the T zirkons with 0,1 aluminiumoxid try it. Ill think it has something to do with aluoxide dispensation and light transmission at that point. The wieland zirkon has two stamps ( biaxial) but each is seperate crontrollable uniaxial so maybe the aluoxide is in better dispensation so you dont have to push sintertemperature up to 1550 or 1600 degrees.By two crontrolled stamps you get maybe although a good grain distribution and height of the blank is only 20 % of diameter that counts more for fit especally if both stamps can be controlled.These are only my thoughts try to find more information.