Secomax™ MDT, a combination that is hard to beat 04:04

The common PCBN inserts in shapes according to ISO standards are not always suitable for machining grooves and the shape of the components severely limits their use. In order to machine all surfaces, groove-turning inserts are needed.

Designed to accommodate narrow cutting edge widths in grooving and parting-off operations, Seco’s MDT (Multi-Directional Turning) system has traditionally consisted of single-sided PCBN inserts, as well as mono and modular tool holders for radial internal, external and axial machining. This range is continuously growing.

At the same time, stability and accuracy in positioning are required. The patented Secoloc™ serrations between the holder and insert make SECO MDT the most rigid groove-turning system on the market.

Almost everything is possible: grooving, copying, turning, plunging, face and internal machining. With SECO MDT and Secomax™ PCBN you can machine hardened grooves and surfaces that are usually difficult to reach.

The edge quality and selected Secomax™ PCBN grades guarantee excellent surface finish and long tool life. The stability and positioning accuracy of SECO MDT allows machining to close tolerances with high cutting data. Secomax™ MDT inserts are available in the grades CBN010, CBN170 and CBN200.

For more information, please contact your local Seco representative, or our Advanced material (PCBN/PCD/CERAMIC) team.

Author: Per Ola Jönander Product Specialist SECOMAX PCBN/PCD/CERAMIC SECO TOOLS AB 737 82 Fagersta, Sweden Office +4622340818 Mobile +46703163555 email:perola.jonander@secotools.com

The influence from hardness of tool life in finish hard turning 00:18

If I don’t get the same tool life every time I run a CBN insert, what can the reason be? Everything is the same; the component, the machine, the insert!

Have you ever asked yourself this question? If so, you are not alone.

Let’s analyse the machining process in more detail. The term “process factors” is used to describe the input to the machining operation (ie all that is needed to be able to generate chips), and includes insert, machine, material etc, see figure.

Many automotive components are case hardened, and on the drawings, the required hardness after case hardening is usually specified to 60 ± 2 HRC. So, if the components are 58 HRC or 62 HRC, will this influence tool life?

To study this, 5 different materials were produced, one reference material and five different variants. After quenching, the reference material was tempered at 160 degrees C. By tempering the material at other temperatures, the hardness is changed.

For each of the workpiece materials, machining was done at the following data:

 - Insert

• CNGA120408S-01525-L1-B, CBN060K 

- Cutting data

• Cutting speed 200 m/min 
• Feed rate 0.15 mm/rev 
• Depth of cut 0.10 mm 

- Tool life criterion

• Breakage 

Tool life in the reference material (60.5 HRC) was set to 100%. When increasing the hardness to 62 HRC tool life is decreased slightly, while when decreasing the hardness, tool life increases.

 As can be seen in the graph, tool life is relatively stable in the 58 – 62 HRC range, but changing the hardness from 62 to 58 HRC, will increase the tool life. A further decrease in the workpiece material hardness increases the tool life even more.

So, to answer the question, tool life of an insert depends on the cumulative effect of all the “process factors”. If any of these factors change, like to hardness of the workpiece material (even though it is still within the approved range) there can be a change in tool life. In the test above, tool life is changed by 20%, but the actual value will always depend on the specific application.

For more information, please contact your local Seco representative, or our Advanced material (PCBN/PCD/CERAMIC) team.

Author: Henrik Sandqvist Product Specialist SECOMAX PCBN/PCD/CERAMIC SECO TOOLS Shanghai CO., Ltd. Level 2, Building 8, 456 HongCao Rd., Shanghai 200233, China Office: +86 21 5426 5849 Mobile: +86 185 1520 6942 e-mail: henrik.sandqvist@secotools.com

PCBN Technical Guide 02:17

The Seco Tools Navigator set include product catalogues for:

• Turning
• Milling
• Holemaking
• Threading
• Solid End Mills
• Tooling
• Seco Capto 

These catalogues give you information about the current product range as well as dimensions on all products, available spare parts etc. The catalogues also give you general cutting data recommendations.

For successful implementation and usage of PCBN, more technical competence is usually needed. To support our PCBN customers, we have for many years also produced a “PCBN Technical Guide”.

It is not a catalogue where you can find products, but rather a guide on how to successfully use PCBN. It is divided in two main parts. The first part is a general technical guide, including:

• Information about PCBN grades
• Where PCBN can be used
• Machining methods
• Insert technologies
• Tooling technologies
• Etc.

In the first part, the different material groups where PCBN can be used are described shortly. The second part is divided into material chapters. In each of the chapters, a more in-depth presentation is made of each workpiece material, including also machining recommendations such as:

• Grade selection
• Cutting data recommendations
• Edge preparation 

 Included in each workpiece material chapter is also a number of application examples, showing successful implementations of PCBN.

 The grade selection is based on the operation (roughing or finishing), the machining method (turning, milling etc), and if it is continuous or interrupted, see table below.

The cutting data recommendations are also based on the operation, the machining method, and are shown as a working window with cutting speed and feed rate.

Below is an application example of machining crushing cones.

 The first Technical Guide was small when it was released in 2003, but our knowledge and experience has increased since then, and the current version, IV, released 2010, contains over 200 pages of useful information for anybody using PCBN.


Click here to download your copy of PCBN Technical Guide.



For more information, please contact your local Seco representative, or our Advanced material (PCBN/PCD/CERAMIC) team.

Author: Henrik Sandqvist Product Specialist SECOMAX PCBN/PCD/CERAMIC SECO TOOLS Shanghai CO., Ltd. Level 2, Building 8, 456 HongCao Rd., Shanghai 200233, China Office: +86 21 5426 5849 Mobile: +86 185 1520 6942 e-mail: henrik.sandqvist@secotools.com