Our Blog

1.2316 Annealed Steel: Annealed vs Prehardened Selection Guide

Most mold manufacturers are accustomed to ready-to-use prehardened 1.2316 at 28–34 HRC. However, annealed 1.2316 (20–25 HRC) has irreplaceable application scenarios, especially if you need custom heat treatment, machine ultra-complex cavities, or perform extensive mold modification and welding. Delivered 1.2316 annealed steel is engineered for these demands. This article covers annealing principles and application screening to clarify when annealed stock is the superior choice.

Table of Content

Hot product

1.2316 Annealed Steel
1.2316 Annealed Steel
DIN 1.2316
DIN 1.2316
1.2316 steel turned bar
1.2316 steel turned bar
1.2316 steel milled surface
1.2316 steel milled surface
1.2316 milling service
1.2316 milling service
1.2316 material milled surface
1.2316 material milled surface

What Is 1.2316 Annealed Steel? Annealing Process & Hardness Logic

 
Annealing is a standard step in mold steel production. All forged mold steel requires annealing to eliminate forging stress, lower hardness and boost cutting performance.
 
Standard annealing procedure for 1.2316: Heat to 860–880°C, hold fully (1 hour per 25mm thickness), furnace cool slowly at ≤30°C/h below 500°C, then air cool out of furnace.
 
Full annealing softens 1.2316 to 20–25 HRC (approx. HBW 220–260), delivering minimal internal stress, optimal machinability and near-equilibrium microstructure. Compared with 28–34 HRC prehardened steel, annealed 1.2316 simplifies milling and deep hole machining for complex cavities, extending tool service life by 30–50%.
 

1.2316 Annealed vs Prehardened Steel: Comparison Chart for Selection Logic

 
Choosing between the two delivery states depends on your machining workflow, not which grade is universally better.
 
If you own mature heat treatment equipment (in-house vacuum furnace or reliable outsourced service), annealed steel offers maximum process flexibility. Post-machining custom heat treatment can reach hardness up to 40–48 HRC, higher than prehardened stock.
 
Small and medium mold shops without heat treatment capacity or tight delivery schedules should select prehardened steel for convenience.
 
Annealed 1.2316 mold steel cuts machining costs significantly: its soft 20–25 HRC matrix reduces carbide tool wear, lifting roughing efficiency by 30–50% and delivering superior finishing surface quality. The tradeoff is scheduling heat treatment and accepting potential distortion risks.
Comparison Item1.2316 Annealed Steel1.2316 Prehard Steel
Delivery Hardness20–25 HRC28–34 HRC
Direct Machining After DeliveryYesYes
Post-Machining Heat Treatment RequiredYes (quenching + tempering)No
CNC Tool LifeHigh (+30–50%)Moderate
Heat Treatment Equipment NeededYesNo special equipment
Lead TimeLong (includes heat treatment cycle)Short
Hardness AdjustabilityCustomizable (20 → 40–48 HRC)Fixed at 28–34 HRC

 

Full Heat Treatment Workflow for 1.2316 Annealed Steel

 
You take full control of post-processing heat treatment with annealed stock.
 
Typical workflow: Receive DIN 1.2316 annealed steel (20–25 HRC) → rough machining (leave 0.3–0.5mm finishing allowance) → quenching: Austenitize at 1030–1050°C, hold by section thickness, oil cool or high-pressure gas cool → temper at matched temperatures for target hardness:
 
200°C → 46–48 HRC; 300°C → 42–44 HRC; 400°C → 38–42 HRC; 500–550°C → 32–36 HRC
 
→ precision finish to final dimensions → optional stress relief temper at 200°C for 2 hours.
 
During quenching, phase transformation from austenite to martensite causes 0.1–0.3% volume expansion. Complex cavity geometries trigger uneven distortion, which is why finishing stock is reserved for post-quench machining. Experienced heat treatment suppliers limit distortion within 0.05–0.10%.
 

Three Ideal Scenarios for 1.2316 Annealed Steel

 
  1. Molds requiring custom high hardness: Engineering plastic injection molds demanding 40–48 HRC wear resistance cannot rely on 28–34 HRC prehardened stock. Annealed steel paired with in-house heat treatment is the optimal solution.
  2. Ultra-complex cavity molds: Deep ribs, thin walls and narrow slots lead to frequent tool breakage and long machining cycles on prehardened steel. Soft 20–25 HRC annealed steel handles intricate cutting effortlessly before hardening.
  3. Refurbished molds needing welding repair: Patch welding on old molds works best on annealed stock, with low base hardness, minimal welding stress and easy post-weld stress relief. Welding on 28–34 HRC prehardened steel creates severe hardness fluctuations in heat-affected zones and weakens repair performance.
 
Annealed steel is not cost-effective for: Standard injection molds with 28–34 HRC service requirements and no heat treatment steps; rush orders with lead time under two weeks; factories without trusted heat treatment vendors.

FAQ:

Q1: Is 28 HRC normal for delivered 1.2316 annealed steel instead of 20–25 HRC?

A: No. Standard annealed hardness ranges 20–25 HRC. A reading of 28 HRC means the supplier shipped prehardened steel by mistake. Contact the supplier immediately to confirm delivery state. Do not machine it directly; machining parameters for 28 HRC and 20–25 HRC differ drastically and cause severe tool loss.

A: No. 20–25 HRC lacks sufficient wear resistance for injection molds, leading to fast cavity abrasion and edge collapse after high shot counts. Annealing only softens steel for machining. Quenching and tempering are mandatory to raise hardness to the usable 28–48 HRC window.

A: Both share similar 20–25 HRC annealed hardness, yet 1.2316 contains 16% chromium for stainless corrosion resistance, even in annealed state (final hardness depends on post heat treatment). P20 holds no high chromium and offers zero anti-corrosion performance in annealed or quenched conditions. Material selection hinges on corrosion resistance demands.

Conclusion

Heat treatment is not a complicated barrier, nor is annealed steel an inferior option. A matched machining workflow enables annealed steel to deliver superior comprehensive mold performance. If you hesitate between annealed and prehardened 1.2316, engineers at Keyspark Steel will analyze your equipment capacity and mold requirements for cost-effective material selection to avoid unnecessary losses.

 

📧 Email: Sales@keysparksteel.com
📱 Mobile/WhatsApp: +86 150 2405 6480

Related Posts