Hot runner nozzle nozzle tip

Product overview
Plastic injection molding uses a hot runner to transport molten plastic and inject it into a mold via a hot runner nozzle. These nozzle tips are manufactured from TZM (titanium‑zirconium‑molybdenum) and optimized to ensure consistent heat transfer, wear resistance and long service life in hot runner applications.

Key advantages

• High thermal conductivity: ≈ 140 W/mK
• High resistance to temperature and corrosion
• Extended service life with optional SHN surface hardening
• Good mechanical workability compared with hard carbides

Material and thermal performance
TZM provides a balance of high thermal conductivity and mechanical resistance. With around 140 W/mK TZM transfers heat effectively at the nozzle tip where no local heating is present. Compared to common tool steels and to copper, TZM combines improved heat transfer with superior mechanical and abrasive resistance. TZM is also generally easier to machine than tungsten carbides.

SHN surface hardening
The SHN gas‑phase diffusion process produces a permanent, strongly adherent diffusion layer on TZM components. SHN increases surface wear resistance—particularly useful with abrasive or glass‑fibre‑reinforced plastics—while preserving the machinability of the substrate. SHN layers show better adhesion and exact surface contour reproduction compared with conventional PVD/CVD coatings.

Function and typical design notes
Hot runner nozzles are heated externally (heating coils) and the nozzle tip must transfer heat to the plastic melt at the mold entry. Therefore nozzle tip material must combine thermal conductivity with mechanical and corrosion resistance; TZM‑based tips meet this requirement.

Microstructure / inspection
Microsections of SHN‑treated TZM tips show a diffusion‑hardened surface layer providing wear resistance while the substrate remains machinable.

Applications

• Hot runner nozzles for plastic injection molding (general‑purpose and fibre‑reinforced plastics)
• Situations requiring high thermal conductivity and high surface wear resistance

Technical specifications

• Material: TZM (titanium‑zirconium‑molybdenum)
• Thermal conductivity: approx. 140 W/mK
• Temperature resistance: very high (suitable for hot runner conditions)
• Corrosion resistance: high
• Surface hardening option: SHN gas‑phase diffusion layer
• Coating adhesion: SHN layers adhere better than conventional PVD/CVD
• Workability: good mechanical workability; easier to machine than tungsten carbide in many cases
• Intended use: nozzle tips for hot runner nozzles in plastic injection molding