Frequently Asked Questions

Below is a list of answers to frequently asked questions (FAQs). If you are unable to find the answer to your question in the FAQs, please contact us

General FAQs

What is the difference between hexagonal boron nitride and cubic boron nitride?

In simple terms, hexagonal boron nitride, hBN, is very similar to graphite. It is the most stable and soft among BN polymorphs, and is therefore used as a filler, lubricant and an additive to cosmetic products. The cubic boron nitride, cBN, has similar crystal structure as diamond, and is the second- hardest known material after diamond. 

We do not supply cBN within Saint-Gobain Boron Nitride.

What is pyrolytic boron nitride? Do you supply PBN?

Pyrolytic boron nitride, or PBN, is hexagonal boron nitride synthesized and grown on a substrate via chemical vapor deposition.

Here at Saint-Gobain we do not supply PBN. 

How do I obtain samples for evaluation?

While filling out the Contact Us form, select "Sample Request" under "Inquiry Type". Make sure to give us a brief description of your application and your project timeline so we can best help you. Please note our typical sample size for powders is 1 lb. and for coatings is an 8 oz. sample jar.

I have made the grade selection, and I am ready to place the order. How do I go about it?

Contact our team at for a formal quotation for the quantities you require, if you haven’t done so already. You may then make your PO to:

Saint-Gobain Advanced Ceramics
168 Creekside Drive
Amherst, NY 14228  

Make sure to include the Quote number, and send the PO directly to for the fastest processing. 

All forms needed for placing an order, making a payment, applying for our standard Net 30 terms, and your supplier database can be found here:  Saint-Gobain Boron Nitride Customer Onboarding

Are you ISO certified? Where can I find your ISO certificates?

Our Boron Nitride manufacturing plant is ISO 9001 and ISO 14001 certified. ISO certificates are available in our document center, and through the links below.

ISO 9001:2015

ISO 14001:2015

Do you have food contact approval?

Yes, we have food contact approval under the conditions outlined in FCN 289 and FCN 856. This coverage under the FDA extends to the EU and Mercosur

Powders FAQs

What is the benefit of using different particle shapes, such as platelets or sphericals?

Platelets tend to align in the direction of resin flow, and due to its inherent anisotropy, offer a very good in-plane thermal conductivity.  Platelets also allow for the addition of BN to systems that require a very thin layer or bond line that would be too big to allow agglomerates to be added. 

Agglomerate grades - where small BN platelets are randomly oriented in all directions, like a snowball - overcome this limitation making BN an isotropic filler suitable for in-plane as well as through-plane thermal conductivity improvements.  Spherical Agglomerates (SA grades) are our most our most popular, and have the benefit of high flowability, packing, and tight particle size distribution. 


What particle size or distribution do I need for my application?

You should be sure that the largest particle size does not exceed the intended thickness or cross section of the final product. It isn’t uncommon for formulators to mix more than one size distribution to achieve better packing of the BN particles and optimal percolation in the resin matrix. 

Why is mixing/dispersion shear important to my grade selection?

Platelet grades are single-crystal BN particles, that are small but robust, and do not break down under high shear forces. Platelet grades are suitable for high shear operations like twin screw compounding and extrusion.

Spherical and agglomerated grades, on the other hand, are comprised of multiple small boron nitride platelets, held together by interlocking planes without addition of any binder system. This makes these grades particularly susceptible to breaking apart when subjected to high shear. These grades are suitable for low-medium shear mixing operations.

How much powder do I need to put in my polymer to increase its thermal conductivity?

The best results occur when there is percolation of the filler particles through the thickness of the composite. This creates a continuous thermal pathway along the filler particles, which will boost the thermal conductivity much more than a system without good particle-to-particle contact. The percolation threshold should be considered when determining the amount of filler to add to the system.

What factors should I consider for improvement in thermal conductivity of a polymeric system?

Boron nitride grade selection for thermal conductivity improvement typically depends on 3 key factors:

  1. Particle size tolerance of your resin system (or bond line thickness)
  2. Desired plane of thermal conductivity improvement (in-plane or through-plane)
  3. Mixing/dispersion process employed (high shear or low/medium shear)

Why use BN instead of graphite or other solid lubricants?

BN is white, non-toxic, stable, and inert. It is oxidation resistant up to about 900°C (unlike graphite, which oxidizes below 500°C). BN keeps its lubricity above 500°C, which is the limiting temperature for graphite as a solid lubricant in air. BN also retains it lubricity in inert or vacuum conditions.

In addition, boron nitride has a low dielectric constant, making it an ideal material for insulation, protection and low dielectric loss.  

What makes BN powders so soft and lubricious?

Boron nitride powders are the lamellar form of BN, which resembles graphite.  Each powder particle is a platelet made up of many layers. Each layer is a flat plane of covalently bonded boron and nitrogen atoms in a hexagonal pattern. While the bonds within each layer are strong, the forces keeping those layers together, called Van der Waals forces, are very weak, causing the soft and lubricious effect when the platelets are rubbed or sheared, and the layers cleave apart.  

Additionally, the surfaces of high purity Saint-Gobain BN crystals are free of carbon and other impurities, and therefore there is no “drag” or sticky feeling when used in cosmetic formulations.

How do different grades impact the properties of a cosmetic formulation?

The key difference is in particle size and crystal morphology. All grades are high purity and pass global regulations for heavy metals.  With grades ranging from 2 to 30 microns in average diameter, the appearance will change as well, going from a matte white appearance to a more translucent or shiny appearance as platelet diameter increases.

Single platelets of high purity hexagonal BN appear transparent when viewed through the platelet face.  This can be seen visually on large platelets, which appear to sparkle when light reflects off the platelet face.  Most fine mesh BN powders form agglomerates that, if not dispersed, appear white and opaque. 

How much powder is typically used in a cosmetic formulation?

The amount of BN filler in a formulation is completely up to formulator, the application, and desired results. BN is typically added to cosmetic formulations from 3 – 10%.

What is the standard packaging and lot size for BN powders?

Standard packaging for boron nitride powders is 25 kg in cardboard boxes or drums. Depending on the grade, our manufacturing lot sizes could be between 250 lbs to 1200 lbs.

Coatings FAQs

What is the difference between the coating grade?

The main difference is the type of binder, but there are also various levels of BN content, pH and total solids content. The datasheet lists our commercially available grades as well as their differences.


What is the difference between grades SF+ and 10SF+?

Grade SF+ is concentrated, thick coating with yogurt-like consistency.  This material must be diluted before being applied by spraying and many of our customers routinely dilute it before they apply by brushing. Type 10SF+, on the other hand, is a ready-to-apply, thinner formulation that eliminates the messiness of diluting on site.

What is the highest temperature these coatings can tolerate?

Type SF+ and 10SF+ can operate at the highest temperature (over 1500°C) in N2 or inert environments. BN in all of our coatings starts to oxidize in air at around 900°C.

Do you have recommended application guidelines for applying CeraGlide BN coatings?

Yes, our CeraGlide Best Practices bulletin outlines recommendations for applying our coatings in detail. Whether spraying, brushing, or dipping, it is common practice to conduct trials with your specific substrate and application method to find the best conditions. Preheating the substrate to 100-200°F can help improve adhesion and reduce drying times for all coating grades. Once the coating is dry and has reached the desired thickness (we recommend building up layers with approx. 0.001" thickness), the coating is ready to use - no bake-out is required.


What is the shelf life of BN coatings, and what are the recommended storage conditions?

Shelf life for BN coatings is 1 year for an unopened container. The coatings should be stored in a tightly sealed container at room temperature. 


What packaging is available for BN coatings (capacity, shape, dimensions)?

Our coatings are available in the following packaging options:


Packaging and Shiping Matrix
Unit Volume Sold Packaging Packaging Approx. Approx.
Plastic Pail Increments Container Shipping Weight Product Weight
1 Gallon 1 Gallon Carton 12 lb 10 lb
4 Gallon Carton 46 lb 40 lb
24 Gallon 

Wooden Crate

315 lb 240 lb
33" x 33" x 22"
32 Gallon Wooden Crate 403 lb 320 lb
33" x 33" x 22"
48 Gallon Wooden Crate 584 lb 480 lb
33" x 33" x 30"
5 Gallon 5 Gallon Carton 55 lb 50 lb
  Wooden Crate 370 lb 300 lb
33" x 33" x 22"



Packaging and Shipping Matrix - Metric
Unit Volume Sold Packaging Packaging Approx. Approx.
Plastic Pail Increments Container Shipping Weight Product Weight
3,8 Liters 3,8 L Carton 6 kg 5 kg
15,2 L Carton 21 kg 8 kg
91,2 L Wooden crate 143 kg 109 kg
838mm x 838mm x 559mm
121, 6 L Wooden Crate 183 kg 146 kg
838mm x 838mm x 559mm
182,4 L Wooden Crate 266 kg 218 kg
838mm x 838mm x 762mm
19 Liters 19 L Carton 25 kg 23 kg
114 L Wooden Crate 168 kg 136 kg


Machinable Ceramic FAQs

What is the difference between the various grades?

Our Combat® boron nitride grades are differentiated based on their composition, and therefore the specific properties they offer.

  • AX05 is the industry leading high purity grade, ideal for the highest temperature applications.
  • Grade HP and A are our standard purity grades that offer improved strength due to the binder phase.
  • M and M26 are composites of BN and silica, commonly used in low-loss, high frequency shielding applications.
  • ZSBN is a composite of BN, silica and zirconia, giving it high wear & corrosion resistance well suited for metal forming applications.

Please contact us for help with grade selection for your application. 

What makes boron nitride ceramic resistant to thermal shock?

The coefficient of thermal expansion for BN is so small that it is nearly zero, giving it dimensional stability across a wide range of temperatures. Coupled with its low thermal mass, due to instrinsically high thermal conductivity and low density (about 50% lower than alumina), BN is virtually unaffected by rapid increases and decreases in temperature.

Are boron nitride machinable ceramics anisotropic?

The pressing process to create a solid BN block induces some alignment of BN platelets in the process.  This creates properties of the material that can vary based on the orientation of that part relative to the pressing direction.  The difference in values of several properties in parallel and perpendicular to the pressing direction can be noted in the technical data sheet on the product page.

Learn more on directionality of boron nitride machinable ceramics.

How can I ensure that my parts will be machined in the desired direction given that BN is an anisotropic material?

It is important to know the properties critical to your application, so parts are machined in appropriate direction. We encourage you clearly mark the desired directionality in your part drawing as well as PO. Without such specification, we cannot guarantee a particular directionality in your parts.

What are the maximum size parts you can make?

The parent billet for our grades HP, M and M26 are 19” x 19” x 16”. Parent billet size for ZSBN is 19” x 19” x 6”. We can make parts that fit the envelop of the parent billet. 
Due to the unique processing steps of our industry leading, high purity grade AX05, we can make parts that fit the parent billet envelop of 19” x 19” x 16”; however, the maximum wall thickness can not exceed 1.5”.  For example, we cannot supply a rod 12” dia x 12” long, but we can supply a tube 12” OD, 10.5” ID and 12” long.

Do you offer standard sizes of machinable ceramics?

Standard shapes are available for ALL GRADES. Dimensions below are shown in inches. Note that due to the parent billet size limitation, ZSBN square bars & rods are only available with 6" length.

Plates Square Bars Rods
Thickness Width Length Width x Height Length Diameter Length
0.25" 5" 6" 0.25" x 25" 8" or 16" 0.25" 8" or 16"
0.25" 5" 12" 0.38" x 0.38" 8" or 16" 0.38" 8" or 16"
0.25" 10" 12" 0.50" x 0.50" 8" or 16" 0.50" 8" or 16"
0.50" 5" 6" 0.63" x 0.63" 8" or 16" 0.63" 8" or 16"
0.50" 5" 12" 0.75" x 0.75" 8" or 16" 0.75" 8" or 16"
0.50" 10" 12" 1.00" x 1.00" 8" or 16" 1.00" 8" or 16"
0.75" 5" 6" 1.5" x 1.5" 8" or 16" 1.5" 8" or 16"
0.75" 5" 12" 2.00" x 2.00" 8" or 16" 2.00" 8" or 16"
0.75" 10" 12" *ZSBN only available  with 6" length

*ZSBN only available  with 6" length



1.00" 5" 6"
1.00" 5" 12" **Tolerance:

+0.200/-0.000" on diameter

+0.063/-0.00" on length

1.00" 10" 21"



Plates & bars available in saw cut or finished tolerances

Saw Cut Tolerance: +0.250"/-0.000" on ALL dimensions

Finished Tolerance: +/-0.010" on (wdth/thck) / +0.063"/-0.000" length

What are the standard tolerances you offer?

Our standard tolerance for saw cut parts are +0.250 (+6.35mm) / -0.000 (0.0mm). Below are our standard tolerance guideline for machined parts, unless specified otherwise by our customers. 

Standard Tolerances
Part Name Diameter Thickness Length O.D. I.D.
  inches mm inches mm inches mm inches mm inches mm

<0.250" thk w/max dia/width 6")

±0.015 ±0.4 +0.000
n/a n/a n/a
Rods +0.020
n/a +0.063


n/a n/a
(<1" thk)
±0.020 ±0.5 ±0.010 ±0.3 n/a n/a  n/a 
Washer / Ring
(disc w/I.D.; <1" thk)
n/a ±0.010 ±0.3 +0.063
±0.020 ±0.5 ±0.010 ±0.3
Tubes n/a n/a +0.063
±0.020 +0.5 ±0.010 ±0.3
Crucible n/a n/a +0.063
±0.020 +0.5 ±0.010 ±0.3
  Width Thickness Length  
  inches mm inches mm inches mm  
Bars ±0.010 ±0.3 ±0.010 ±0.3 +0.063
n/a n/a
Plates ±0.010 ±0.3 ±0.010 ±0.3 +0.063
n/a n/a




I would like to buy a machined part with intricate features. How do I go about that?

We have machining facilities inhouse that allow us to serve the customers that want machined components. We ask you send us your drawing or sketch with grade reference, directionality preference if any, and tolerance specifications. All Combat® BN grades are easily machined and detailed surfaces, pockets, channels, grooves, holes, threads, etc. can be designed into the finished part. 

I have a machine shop, but I have never machined boron nitride. What do I need to know about boron nitride machining?

The key feature to note is that boron nitride is machined dry - without coolants or lubricants. Most grades can be machined with standard carbide tip tooling. ZSBN requires diamond tipped tooling for efficient operation. 


What is the shelf life of BN machinable ceramics? What are the recommended storage guidelines?

The shelf life for solid BN grades is 3 years. Boron nitride should always be stored in a dry space, tightly sealed, in its original packaging if possible, to avoid exposure to moisture.

I purchased some boron nitride that is past its shelf life. Can I still use it?

Boron nitride ceramic that has been sitting past its shelf life or has not been stored according to the storage guidelines may have picked moisture and will not perform as intended. The best way to use such material is by baking it to ensure it is restored to its original condition. We recommended soaking for 6 hours or longer in Nitrogen at the rate of 10°C/min to 450°C, followed by cooling down at the same rate. If heated too quickly, spalling may take place. Other protecting atmosphere, such as Ar, can also be used. If the materials are in a protecting atmosphere, the soak temperature can be as high as 1200°C.