Moulds and dies are tools that are essential to mass production in present-day manufacturing. Both are key elements in manufacturing―for example, moulds are used in injection moulding to shape resin as well as in casting, and dies are used in stamping. This section introduces observation and measurement examples of moulds and dies using a digital microscope.

Observation and Measurement of Moulds and Dies Using a Digital Microscope

Advantages and disadvantages of using moulds/dies

Advantages
  • Fast mass production of products with the same shape.
  • High-accuracy production with low variation.
  • No special skills required with anyone able to perform operations easily.
  • Minimal material waste and low processing costs.
Disadvantages
  • Mould/die fabrication can be costly and time-consuming.
  • High level of skill and experience required for mould/die fabrication.

Types of moulds/dies

Moulds and dies are tools used to form and shape materials.
Dies are “open” in that they consist of top and bottom pieces that are not sealed.
Moulds, on the other hand, are “closed”, and materials such as metal and resin are poured into a cavity to form a finished product.

Dies

Press dies
Press dies are used to shape automobile bodies and other components. These are the most common type of die. Press dies can also be further categorised into punch dies, bending dies, and compression dies.
Forging dies
These dies are used to shape drive components for automobiles and other vehicles. The dies are used to hit a material and create a different shape. Parts requiring high strength are usually made with forging dies. There are two main forging methods: Hot forging, when the material is heated and softened before being struck, and cold forging, when the material is struck at room temperature.

Moulds

Moulds for injection moulding
These moulds are used for moulding plastic parts. A plastic material is heated in a heating cylinder and then pressurised and injected into a mould. The plastic then cools and solidifies.
Moulds for die casting
Die casting moulds are used for moulding by injecting molten aluminium, magnesium, or other material into a mould under high pressure. This makes it possible to mass-produce casting products with high accuracy and high-quality surface conditions at high speeds. The term “die casting” is generally used to refer to both the casting method and the moulded product.
Casting moulds
Casting is done by heating cast iron, aluminium alloys, copper, brass, or other materials to high temperatures until they melt, and then pouring the molten material into a mould. The mould used for casting is called a casting mould, and the resulting product is called a casting.
Powder mould
Powder moulds are used to form products by compressing and then hardening a metal powder.

Mould/die machining methods

Cutting
Moulds and dies can be machined using an edged tool to cut away the surface of a material. This cutting is most commonly done in a machining centre.
Grinding
Grinding bits can also be used to machine moulds and dies. This method makes it possible to machine hard materials that cannot be machined by cutting, including hardened steel and cemented carbide. Compared with cutting, this method allows for machining with higher accuracy and is commonly used for finishing. However, grinding also takes longer.
Wire electrical discharge machining
Wire electrical discharge machining is a method that uses brass wires to cut metal. With this method, machining is possible regardless of the hardness of the metal, enabling machining of hardened steel materials, cemented carbides, and other metals.

Observation and measurement examples of moulds and dies using a digital microscope

The latest examples of observation and measurement of moulds and dies using KEYENCE’s VHX Series 4K Digital Microscope are introduced below.

Depth composition image of a microneedle mould
VH-Z20, 100×, ring illumination
Depth composition image of a punch die
VH-Z20, 100×, ring illumination
Observation image of the inner wall of a mould

VHX-E20, 20×

  • A: Without backlight
  • B: With backlight
3D image of a screw mould
ZS-20, 50×, ring illumination
Comparison image of the surface texture of a product

ZS-200, 1500×, coaxial illumination

Managing wear is possible by measuring products in 3D.

3D measurement image of the cutting edge of a die
VH-Z20, 200×, ring illumination
3D measurement image of surface defects

ZS-200, 500×, coaxial illumination

Defects that cannot be captured with a roughness meter can be clearly identified.

3D measurement image of marking on a mould
ZS-200, 1000×, coaxial illumination
Observation image of the sliding parts of a mould
VH-Z20, 100×, ring illumination (normal image)

Optical Shadow Effect Mode image

Optical Shadow Effect Mode can be used to visualise microscopic irregularities.

Surface observation image after electrical discharge machining
VHX-E20, 50×, ring illumination (normal image)

Optical Shadow Effect Mode image

Optical Shadow Effect Mode can be used to visualise satin surface patterns.

Optical Shadow Effect Mode colour map image