In the manufacturing process of medical injection molds, the selection of mold steel is undoubtedly a core challenge. Given that plastic molds need to operate at high temperatures ranging from 200-300 degrees Celsius, and their cavities are complex with high requirements for dimensional accuracy and surface roughness, stringent standards are imposed on the machinability, mirror polishing performance, heat treatment deformation control, and dimensional stability of the mold steel. So, how should we choose the appropriate mold steel for injection mold opening? This article will delve into this topic from three dimensions: the performance classification of injection molds, the principles of mold steel selection, and the specific impact of material selection on molds.

1. Mold Steel Selection for Medical Injection Molds: Two Categories Based on Performance Requirements

The selection of mold steel for medical injection molds is primarily divided into two categories based on their performance requirements:

1. Structural Component Steels: This includes the gating system, guide elements, fixed (movable) mold plates, ejector mechanism components, support components, etc. These parts typically use medium or low-carbon carbon structural steels or alloys to meet their basic structural strength and usage requirements.

2. Forming Component Steels: Such as cavities, cores, inserts, etc., which are the key components that directly shape plastic products. Due to the complexity of medical injection mold cavities and the high requirements for dimensional accuracy and surface roughness, the mold steel used for these components must have excellent machinability, mirror polishing performance, as well as good control over heat treatment deformation and dimensional stability.

2. Medical Injection Mold Opening: Core Principles for Mold Steel Selection

When selecting mold steel for medical injection molds, the following core principles should be followed:

1. Superior Comprehensive Mechanical Properties: Forming components need to withstand temperature, pressure, erosion, and wear during operation, so they must have sufficient strength, plasticity, and toughness.

2. Appropriate Hardened Layer Thickness: The surface of medical injection mold cavities should have a sufficiently thick hardened layer to ensure their hardness and wear resistance.

3. Good Machinability: Given the complex shapes of medical injection molds, machining costs often account for a significant portion (about 75%) of the total mold cost. Therefore, the selected steel must have good machinability.

4. Selection Based on Plastic Product Requirements: For large, high-precision injection molds, when the production volume of plastic parts is large, pre-hardened steel should be used to prevent deformation during heat treatment.

3. Mold Steel Selection for Medical Injection Molds: Profound Impact on Molds

1. Improvement in Mold Lifespan: Using materials with high hardness for mold opening will also increase the lifespan of the mold. For example, using steel with a heat treatment hardness of around HRC50 can result in a mold lifespan of 500,000 to 1 million cycles. Otherwise, the mold is prone to wear, and the injected products may deviate from specifications. Therefore, the selected steel must have good heat treatment properties and excellent machinability at high hardness levels.

2. Consideration of Plastic Raw Materials on Steel: The raw materials for injection molding and the fillers added have a significant impact on the steel, especially glass fibers, which cause greater wear on injection molds. Additionally, some plastic materials are corrosive, so these factors need to be comprehensively considered when selecting mold opening materials.

In summary, when selecting mold steel for medical injection molds, Yize Mold fully considers factors such as the customer's estimated production volume, mold production costs, plastic material characteristics, and mold lifespan, to ensure that the selected steel not only meets the performance requirements of the mold but also maximizes its processing performance.

Dongguan Yize Mold Co., Ltd.: Professional Provider of Medical Injection Mold Solutions

Since its establishment in 2007, Dongguan Yize Mold Co., Ltd. has been deeply involved in the fields of precision mold design and manufacturing, as well as precision injection molding production. Headquartered in Dongguan, the manufacturing capital, with convenient transportation and logistics, the company specializes in providing complete solutions for automotive connectors, medical product injection molding, cleanroom injection molding, PFA custom injection molding, and other products, from design, precision mold manufacturing, injection molding and assembly, to after-sales service. For more information or to inquire about cooperation opportunities, please call +86 13302615729 (WeChat, WhatsApp same number), and we will sincerely serve you!