Principles and Practical Guidelines for Selecting Bracket Materials in Hardware System Design

In hardware system design, brackets, as core load-bearing components, undertake the key functions of fixing equipment, distributing loads, and ensuring system stability. The selection of their materials directly determines the structural strength, service life, operational safety, and overall cost of the hardware system. The adaptability of bracket materials is not only closely related to the weight of hardware equipment, installation environment, and operating conditions but also needs to take into account multiple factors such as the material's mechanical properties, corrosion resistance, processing convenience, and economy. Unreasonable material selection can easily lead to bracket deformation, corrosion, fracture, and other faults, which in turn affect the normal operation of the entire hardware system and even cause safety hazards. Combining the characteristics, applicable scenarios, and selection taboos of various commonly used bracket materials, this article systematically elaborates on the principles and practical methods for selecting bracket materials in hardware system design, providing technical reference for engineering designers and helping to improve the reliability and long-term effectiveness of hardware systems.

I. Core Principles for Selecting Bracket Materials

The selection of bracket materials for hardware systems must follow the core principles of "adaptability first, performance compliance, reasonable economy, and convenient maintainability", and comprehensively consider the following four key factors to ensure that the bracket is highly compatible with the operational needs of the hardware system.

First, the principle of mechanical performance adaptability. The bracket must have sufficient strength, toughness, and stability to bear the weight of hardware equipment, vibration loads during operation, and additional forces from the external environment (such as wind force, snow pressure, etc.), avoiding bracket deformation or fracture due to insufficient mechanical properties of the material. Different hardware systems have significant differences in load requirements. It is necessary to calculate key parameters such as the yield strength and tensile strength required for the bracket based on the equipment weight and operating conditions, and select materials with mechanical properties that meet the requirements.

Second, the principle of environmental adaptability. The installation environment of brackets is complex and diverse, which may face harsh conditions such as humidity, high temperature, corrosive media, and ultraviolet radiation. The material must have corresponding weather resistance and corrosion resistance to ensure that no obvious corrosion or aging occurs during long-term use, and the structural integrity of the bracket is guaranteed. For example, brackets installed outdoors need to focus on corrosion resistance, while brackets in indoor humid environments need to focus on moisture and rust resistance.

Third, the principle of economy and practicality. On the premise of meeting mechanical performance and environmental adaptability, it is necessary to take into account the material's procurement cost, processing cost, and installation cost, avoiding cost waste caused by excessive pursuit of high-performance materials. At the same time, the material should have good formability, be easy to cut, weld, and assemble, reducing the processing difficulty and construction cost of the bracket and improving installation efficiency.

Fourth, the principle of long-term effectiveness and maintainability. As a long-term load-bearing component of the hardware system, the bracket must have a long service life, reducing the frequency and cost of later maintenance. The material should be easy to inspect and maintain; if local damage occurs, it can be repaired conveniently, avoiding maintenance difficulties caused by material characteristics that affect the normal operation of the hardware system.

II. Characteristic Analysis and Selection Evaluation of Commonly Used Bracket Materials

At present, the commonly used bracket materials in hardware system design mainly include cast iron, angle iron, galvanized angle steel, and aluminum alloy. Various materials have significant differences in mechanical properties, corrosion resistance, processing characteristics, and applicable scenarios, which need to be evaluated one by one according to design requirements to select the optimal solution.

(I) Cast Iron: Not Recommended for Hardware System Brackets​

Cast iron is a general term for alloys composed of iron, carbon, and silicon. Its core feature is that the carbon content exceeds the amount that can be retained in the austenite solid solution at the eutectic temperature, belonging to traditional metal materials. From the perspective of the usage requirements of hardware system brackets, cast iron has obvious performance defects and is not suitable as a bracket material.​

In terms of mechanical properties, the as-cast plasticity and toughness of carbon steel castings are low, their ability to bear impact loads and vibration loads is weak, and they are prone to brittle fracture, which cannot meet the core requirement of the bracket for structural stability and is not suitable for direct use in the production of hardware system brackets. In terms of service durability, cast iron is prone to oxidative rust during use, especially in humid environments with corrosive media, the rusting speed accelerates, which will gradually reduce the structural strength of the bracket and easily cause safety hazards in long-term use. In addition, cast iron has poor formability and high welding difficulty, which is not conducive to the personalized processing and installation adjustment of the bracket. Based on the above factors, cast iron is not recommended as a bracket material in hardware system bracket design.​

(II) Angle Iron: Not Suitable for Long-Term Operating Hardware Brackets​

Angle iron, commonly known as angle steel, is a long strip of steel with two sides perpendicular to each other at a right angle, belonging to a commonly used section steel material. However, its performance characteristics determine that it is not suitable for long-term operating hardware system brackets.​

The core defect of angle iron is poor corrosion resistance. It is prone to rust during long-term use, especially in outdoor or humid environments. Rust will gradually erode the steel body, leading to reduced bracket strength and structural looseness, affecting the stability of the hardware system. At the same time, the welding performance of angle iron is poor. Due to its high carbon content, poor plasticity, and uneven structure, various defects are likely to occur during welding: white structure is easy to occur after welding, leading to increased brittleness of the welding part; cracks are easy to occur in the weld seam, reducing welding strength; pores are also easy to occur after welding, affecting the sealing and reliability of the welding. In addition, although the mechanical properties of angle iron can meet the short-term support needs of some light-load equipment, under long-term operation, its fatigue resistance is insufficient, and it is prone to bracket deformation due to vibration and load changes. After comprehensive consideration, angle iron is not used as the preferred material for hardware system brackets, and can only be used for temporary support or simple brackets in non-critical parts, and additional strict anti-corrosion measures must be taken.​

(III) Galvanized Angle Steel: Preferred Material for Medium-Heavy Load and Outdoor Scenarios​

Galvanized angle steel is a section steel made by galvanizing the surface of angle steel, which is divided into two categories: hot-dip galvanized angle steel and cold-dip galvanized angle steel. Among them, hot-dip galvanized angle steel is more widely used in hardware system bracket design due to its better performance. Cold-dip galvanizing coating mainly ensures full contact between zinc powder and steel through electrochemical principles, and uses the electrode potential difference to achieve corrosion prevention; hot-dip galvanized angle steel, also known as hot-dipped galvanized angle steel, forms a uniform galvanized layer on the surface by immersing the angle steel in molten zinc liquid, which has better corrosion resistance and structural reliability.​

The core advantages of galvanized angle steel are reflected in three aspects: first, low processing cost. The anti-rust cost of hot-dip galvanizing is much lower than that of other paint coating anti-corrosion treatments, which can effectively control the processing cost of the bracket; second, durability. Hot-dip galvanized angle steel has a shiny surface, uniform zinc layer, no missing plating or dripping, tight combination between the galvanized layer and steel, strong adhesion, and outstanding corrosion resistance—in suburban environments, the standard thickness of hot-dip galvanized anti-rust layer can be maintained for more than 50 years without repair, and in urban or offshore areas with slightly stronger corrosion, it can also maintain an anti-rust effect for more than 20 years, which can meet the long-term operation needs of hardware systems; third, good reliability. The galvanized layer forms a metallurgical bond with the steel, becoming part of the steel surface, so there will be no problem of coating peeling, and the durability and stability of the coating are more guaranteed.​

Combined with industry application standards, the thickness of the hot-dip galvanized layer of galvanized angle steel must meet relevant specification requirements. For example, in outdoor hardware systems such as photovoltaic brackets, the thickness of the galvanized layer usually needs to reach more than 85μm, and the salt spray test life needs to reach more than 30 years to ensure the anti-corrosion effect in complex outdoor environments. Galvanized angle steel has excellent mechanical properties, high strength, and strong load-bearing capacity. It can be flexibly processed by cutting, welding, etc., to adapt to the design of hardware brackets of different sizes and loads. It is especially suitable for medium-heavy load equipment and outdoor-installed hardware system brackets, such as photovoltaic power station equipment brackets and industrial equipment brackets.​

(IV) Aluminum Alloy: Ideal Material for Light-Load and High-Requirement Scenarios​

Aluminum alloy is one of the most widely used non-ferrous metal structural materials in industry, and has been widely used in aerospace, automotive, machinery manufacturing, shipbuilding, and chemical industries. With the development of hardware systems towards lightweight and high precision, the application of aluminum alloy in bracket design is becoming more and more extensive. Aluminum alloy is made of aluminum as the base material with a small amount of alloying elements (such as magnesium, silicon, copper, etc.), and its performance characteristics are highly consistent with the lightweight and high-reliability requirements of hardware system brackets.​

The core advantages of aluminum alloy are very prominent: first, low density and light weight. Its density is only about 1/3 of that of steel, which can significantly reduce the self-weight of the bracket and the overall load of the hardware system. It is especially suitable for weight-sensitive scenarios such as roof installation and portable equipment, and is also convenient for the transportation and installation of the bracket; second, excellent mechanical properties. Although the density is low, the strength is high, close to or exceeding that of high-quality steel. Some aluminum alloys can obtain good mechanical properties, physical properties, and corrosion resistance through heat treatment, which can meet the support needs of light-load and medium-load hardware equipment; third, good formability. It has excellent plasticity and can be processed into various profiles and plates, which is convenient for customizing brackets of different shapes and sizes according to the structural needs of the hardware system, with low processing difficulty and high efficiency; fourth, excellent comprehensive performance. It has excellent electrical conductivity, thermal conductivity, and corrosion resistance, strong weather resistance, and is not easy to rust. It does not require complex anti-corrosion treatment, and has a colorful decorative property, which can adapt to hardware systems with certain appearance requirements; in addition, aluminum alloy also has the characteristics of impact resistance, fire resistance, moisture resistance, sound insulation, heat insulation, and good vibration resistance, which can adapt to various complex installation environments.​

According to industry standards, the aluminum alloy commonly used for hardware system brackets preferably selects 6063-T6 profiles, whose yield strength is ≥215MPa, the thickness of the anodic oxidation film is controlled at 5-25μm, the hardness needs to reach more than HV800, and there is no obvious corrosion after 2000 hours of salt spray test, which can meet the long-term operation needs of most light-load hardware systems. Aluminum alloy brackets are suitable for light-load equipment, high-precision equipment, outdoor humid environments, or hardware systems with strict requirements on bracket weight, such as electronic equipment brackets, precision instrument brackets, and roof photovoltaic brackets. However, due to their relatively high cost and slightly lower load-bearing capacity than galvanized angle steel, they are not suitable for heavy-load equipment brackets.

III. Practical Process and Precautions for Bracket Material Selection

Combined with the above analysis of material characteristics, the selection of bracket materials in hardware system design must follow the practical process of "demand analysis—material screening—performance verification—cost evaluation" to ensure that the selected materials not only meet the design requirements but also have economy and maintainability.

Step 1: Clarify design requirements. First, determine the weight of the hardware equipment, operating conditions (such as whether there is vibration or impact), installation environment (such as indoor/outdoor, humid/dry, whether there are corrosive media), calculate the load-bearing capacity and mechanical performance parameters required for the bracket, and clarify the bracket's size, structural form, and service life requirements, laying the foundation for material selection.

Step 2: Preliminary material screening. According to the design requirements, exclude materials that do not meet the performance requirements (such as cast iron and angle iron), and screen from suitable materials such as galvanized angle steel and aluminum alloy. For example, galvanized angle steel is preferred for heavy-load and outdoor scenarios; aluminum alloy is preferred for light-load, weight-sensitive, and high-precision scenarios. At the same time, it is necessary to select materials and surface treatment methods with matching corrosion resistance according to the anti-corrosion requirements of the installation environment. For example, hot-dip galvanized angle steel can be selected for outdoor scenarios, and aluminum alloy or galvanized angle steel with enhanced anti-corrosion treatment can be selected for humid environments.

Step 3: Performance verification. Verify the mechanical properties, corrosion resistance, and processing performance of the selected materials to ensure that parameters such as the material's yield strength, tensile strength, and corrosion resistance meet the design requirements. For example, for galvanized angle steel, it is necessary to verify the thickness, adhesion, and anti-corrosion life of the galvanized layer; for aluminum alloy, it is necessary to verify the mechanical properties and corrosion resistance after heat treatment to ensure that the bracket will not experience performance degradation during long-term operation.

Step 4: Cost evaluation and optimization. On the premise of meeting performance requirements, compare the procurement cost, processing cost, installation cost, and later maintenance cost of different materials, and select the material with the best cost performance. For example, for medium-heavy load outdoor brackets, the cost of galvanized angle steel is lower than that of aluminum alloy, and its load-bearing capacity is stronger, so it can be preferred; for light-load high-precision brackets, although aluminum alloy has a higher cost, it can reduce the overall load and improve installation efficiency, with better comprehensive cost performance.

In addition, the following two points should be noted in material selection: first, avoid blindly pursuing high-performance materials, and select reasonably according to actual needs to prevent cost waste; second, pay attention to material compatibility. The bracket material must match the installation method and fixed components of the hardware equipment to ensure that the bracket is firmly installed and easy to disassemble, facilitating later equipment maintenance and bracket inspection.

IV. Conclusion​

The selection of bracket materials is a key link in hardware system design, which is directly related to the stability, safety, and service life of the system. In actual design, it is necessary to abandon materials with substandard performance such as cast iron and angle iron, and reasonably select galvanized angle steel or aluminum alloy according to the load requirements, installation environment, and economic requirements of the hardware system—galvanized angle steel, with its excellent corrosion resistance, mechanical properties, and economy, has become the preferred choice for medium-heavy load and outdoor scenarios; aluminum alloy, with its lightweight, high precision, and good comprehensive performance, is suitable for light-load and high-requirement scenarios.​

With the development of hardware systems towards diversification, high precision, and long-term effectiveness, the selection of bracket materials also needs to be continuously optimized. Combining industry standards and technological iteration, it is necessary to balance performance and cost, and pay attention to the environmental adaptability and maintainability of materials. Designers should deeply grasp the characteristics of various materials, strictly follow the selection principles and practical processes, and reasonably select bracket materials to provide reliable structural support for the stable operation of hardware systems, and promote the improvement of hardware system design quality and operational efficiency. In the future, combined with the development of new material technologies, we can explore more advantageous bracket materials, further optimize the performance and economy of brackets, and meet the design needs of hardware systems in different scenarios.