4140 Annealed Cold Rolled Steel: A Guide for Industrial Applications

If you’re in the manufacturing, инженерный, or any industry that requires high – performance metals, 4140 annealed cold rolled steel is a material you should know well. This alloy offers a unique blend of strength, стойкость, и механизм, making it suitable for a wide range of applications. В этом руководстве, we’ll explore everything from its material properties and composition к industrial applications и supply chain options, Помогая принять обоснованные решения для ваших проектов.

1. Свойства материала & Композиция

Химический состав

4140 steel is a medium – углерод, хром – molybdenum alloy. The main alloying elements include:

• Углерод (В): Вокруг 0.38 – 0.43%, which contributes to the steel’s hardness and strength.
• Хром (Герметичный): Примерно 0.80 – 1.10%, Улучшение износостойкости и укрепления.
• Молибден (МО): С 0.15 – 0.25%, it improves the steel’s toughness, especially at high temperatures, and also contributes to hardenability.
• Марганец (Мнжен): In the range of 0.75 – 1.00%, it helps with strength and hardenability as well.

Механические свойства

Например, in a manufacturing plant producing hydraulic cylinders, а 4140 annealed cold rolled steel’s yield strength of 400 МПА (a value within the range) ensures that the cylinder rods can withstand the internal pressure without deforming.

2. Нагревать – Treatment Response & Механические характеристики

Тепловая обработка

• Отжиг: Heating the 4140 steel to around 840 – 870°C and then slowly cooling it. This process softens the steel, reduces internal stresses, and refines the grain structure, enhancing механизм.
• Утомить и отпуск: Heating the steel to austenitizing temperature (вокруг 840 – 860° C для 4140) с последующим быстрым охлаждением (гашение) in oil or water. Затем, it is tempered at 550 – 650°C to balance hardness and toughness. А hardenability curve 4140 сталь shows how the depth of hardening varies with cooling rate.
• Нормализация: Heating above the critical temperature (similar to austenitizing) and air – охлаждение. It improves the grain structure and mechanical properties’ uniformity.

Comparison of Hardness

A manufacturer of high – Стрессовые болты могут выбирать и закаленные 4140 сталь за высокую твердость и прочность, в то время как части, которые требуют большей формируемости и меньшей твердости, отожженная версия предпочтительна.

3. Механизм, Формируемость & Поверхностная отделка

Механизм

• Рейтинг механизма: 4140 Отол, что лучше, чем некоторые выше – Сплавовые стали. По сравнению с 1045 сталь, 4140 отожжен имеет рейтинг вокруг 60 – 70% (где 1018 Горячий свернутый = 100%).
• Рекомендуемые скорости резки: Для поворота операций с высоким – скорость стали (HSS) инструменты, скорость резки 60 – 90 М/мин рекомендуется. При использовании карбидных инструментов, скорости могут быть увеличены до 150 – 250 м/мой.
• Chip control: Due to its relatively soft nature in the annealed state, chip control can be achieved with proper tool geometry. Например, using tools with positive rake angles helps in breaking the chips into smaller pieces during machining.

Формируемость

• Cold forming limits: 4140 annealed can be cold – formed, but it requires more force compared to low – carbon steels. А изгибающий радиус 4140 annealed cold rolled depends on the thickness of the material. Для 5 – mm thick sheet, a minimum bending radius of about 1.5 times the thickness (7.5 мм) is typically recommended.
• Сварка: 4140 steel has fair weldability. Preheating to 150 – 250°C and post – термическая обработка (отпуск) are often required to prevent cracking. MIG or TIG welding with appropriate filler metals like ER80S – G can be used.

Поверхностная отделка

The surface finish achievable on 4140 CR can be as low as Ra 0.2 – 0.8 мкм. This smooth surface finish is beneficial for applications where friction needs to be minimized, such as in shafts and hydraulic cylinder rods.

4. Промышленные применения & End – Варианты использования

• Автомобиль: Automotive crankshafts made from 4140 annealed cold rolled steel can withstand the high – stress cyclic loading during engine operation. Также, высокий – stress bolts & крепеж in engines are often made of 4140 steel due to its strength.
• Аэрокосмическая: Aerospace landing – gear components require materials with high strength – к – weight ratios. 4140 сталь, especially in the heat – treated condition, can meet these requirements. Например, the landing – gear struts can be made from 4140 steel to ensure durability during landing impacts.
• Oil and Gas: Drill collars 4140 сталь are used in drilling operations. They need to withstand high torque and compressive forces, and the strength and wear resistance of 4140 steel make it an ideal choice.
• Промышленная техника: Передачи & шестерни, держатели инструментов & светильники, и валы & ось are commonly made from 4140 сталь. In a gearbox, 4140 pre – hardened gears can transmit high torque efficiently.

5. Доступность, Shapes & Варианты цепочки поставок

Shapes and Sizes

• Round bar sizes: 4140 annealed cold rolled round bars are available in diameters ranging from 3 – 150 мм. Например, a manufacturer of small – scale machinery may use 10 – mm diameter round bars for shafts.
• Flat bar: Thicknesses can range from 1 – 30 мм, and widths from 10 – 200 мм.
• Square & hex bar: Square bars with side lengths of 5 – 100 mm and hex bars with across – flats dimensions of 6 – 80 mm are commonly stocked.

Цепочка поставок

• Точность – ground 4140 rod suppliers: There are many suppliers worldwide that offer precision – ground rods, ensuring tight tolerances. Например, in the US, companies like XYZ Metals specialize in providing precision – ground 4140 стержни.
• Резать – к – длина 4140 annealed service: Many suppliers offer cut – к – length services, allowing customers to order the exact lengths they need. This reduces waste and costs.
• Mill minimum order 4140 Герметичный: The mill minimum order quantity can vary, but it’s often around 1 – 5 тонны. Однако, some suppliers may offer smaller quantities for customers with lower requirements.
• Domestic vs import 4140 доступность: In the US, domestic suppliers can provide shorter lead times, обычно внутри 1 – 2 weeks for standard sizes. Imported 4140 steel may take 4 – 6 weeks but could be more cost – effective for large orders.

6. Стандарты, Сертификаты & Техническая документация

• ASTM A331: This standard covers cold – finished alloy steel bars, включая 4140 annealed cold – finished. It defines the chemical and mechanical property requirements.
• Sae 4140 grade equivalent chart: Helps in comparing 4140 steel with other grades from different standards. Например, it shows the equivalent grades in the European EN system.
• Амс 6381 4140 annealed specification: Спецификация аэрокосмического материала (Амс) that details the requirements for 4140 annealed steel used in aerospace applications.
• В 1.7225 / 42CrMo4 vs 4140: В 1.7225 (42CRMO4) is the European equivalent of 4140 сталь. While they have similar chemical compositions, there may be slight differences in mechanical properties due to manufacturing variations.
• Отчет о тестировании материала (Магистр) 4140: A document provided by the supplier that shows the test results for chemical composition and mechanical properties of the supplied 4140 сталь.
• Iso 9001 & AS9100 certified 4140 supplier: Iso 9001 ensures quality management systems, and AS9100 is for aerospace – related quality. Suppliers with these certifications can provide more reliable products.
• REACH & ROHS Соответствие 4140 сталь: REACH (Registration, Evaluation, Authorization, and Restriction of Chemicals) and RoHS (Restriction of Hazardous Substances) ensure that the 4140 steel does not contain harmful substances above the regulated limits.

Взгляд Yigu Technology на 4140 Annealed Cold Rolled Steel

В Yigu Technology, we’ve witnessed the versatility of 4140 annealed cold rolled steel in various projects. For applications that demand a balance of strength and machinability, like in the production of high – точные шестерни, this material is a top choice. We often recommend it to clients in the automotive and machinery industries. Our team can assist in selecting the right heat – treated state and shape based on your project requirements, ensuring cost – efficiency and high – quality end – продукция.

Часто задаваемые вопросы

1. Может 4140 annealed cold rolled steel be welded easily?

4140 steel has fair weldability. Однако, preheating to 150 – 250°C and post – термическая обработка (отпуск) are often required to prevent cracking. Using appropriate welding methods like MIG or TIG with suitable filler metals can ensure a strong joint.

2. What is the difference between 4140 annealed and 4140 утомил и закален?

4140 annealed is softer, with a hardness of 170 – 210 Бенн, and is more suitable for applications requiring formability and ease of machining. 4140 quenched and tempered is much harder, with a hardness of 40 – 50 HRC (388 – 477 Бенн), and is used for applications where high strength and wear resistance are crucial.

3. Where can I find a reliable supplier for 4140 annealed cold rolled steel?

You can look for suppliers with ISO 9001 or AS9100 certifications, depending on your industry. Domestic suppliers may offer shorter lead times, while imported options could be more cost – effective for large orders. Requesting material test reports (Mtrs) can help ensure the quality of the supplied steel.