1. Introduction

At the same time, the epidemic has pushed companies to focus on building supply chain resilience and sustainability and to shift to diversified and digitalized management to cope with future uncertainties. Many companies have relied too heavily on the “just-in-time” model of supply chain management, resulting in a lack of sufficient response space in case of emergencies. Globally, 60% of companies increased inventory levels during the outbreak, but inventory costs rose by 25-40%. In terms of adaptation, enterprises have taken measures such as digital transformation of their supply chains to improve supply chain transparency and management efficiency through technological means [1, 2]. For example, certain enterprises use big data technology to optimize demand forecasts and reduce inventory backlogs and pressure on the financial chain. In addition, diversified supplier selection has become a key strategy to enhance supply chain resilience, with enterprises no longer relying solely on suppliers in a certain country or region but instead seeking a more decentralized supply chain layout.

In terms of raw material supply, the epidemic has led to the implementation of embargo policies in multiple countries and regions around the world, resulting in disruptions in the production and transportation of key raw materials such as minerals, metals, and semiconductors. Particularly in the global supply network that the manufacturing industry relies on, the supply chain of certain key materials has broken down, leading to serious delays in companies’ production schedules [3]. Industries with a high concentration of suppliers, such as electronics and automotive manufacturing, were particularly hard hit by raw material shortages [4]. Sales and demand fluctuations are even more uncertain in the context of the pandemic [5]. Demand plummeted in some sectors, such as the automotive and luxury goods markets, while the demand in other industries, such as electronics and medical equipment, has sharply increased, posing challenges to sales and inventory management for manufacturing companies. During the pandemic, the sudden change in consumer behavior made it difficult for companies to accurately predict market demand, resulting in a mismatch between product supply and demand. The logistics and transportation chain was also greatly affected. Transportation costs rose sharply due to a significant reduction in global shipping and air transportation, and logistics bottlenecks led to longer delivery times and a significant drop in the overall efficiency of the supply chain. Port congestion and freight delays have severely affected the normal operations of global manufacturing companies and increased supply chain uncertainty. Financial chain management has come under increased pressure as a result of the epidemic. Supply chain disruptions and production stoppages led to reduced revenues, while rising raw material costs and logistics expenses further squeezed profit margins. At the same time, the pressure on the billing period between suppliers and customers increased, and the liquidity of enterprises was challenged, and many enterprises suffered from the crisis of capital chain breakage during the epidemic.

The current academic research has extensively explored the conceptualization of supply chain disruption and resilience. However, there is still a lack of research on more systematic case studies. Based on the above background, this paper intends to explore the major impacts of the epidemic on global supply chain disruptions, the measures taken by the manufacturing industry during the pandemic to enhance supply chain resilience, and how to build the sustainability of future supply chains. This study will select Apple, a typical enterprise in the manufacturing industry, as a case study to explore its supply chain recovery situation from the perspective of its actual supply chain operation.

2. Literature Review

Supply chain disruption refers to the inability of a part of the supply chain to function properly due to various risk factors, which affect the liquidity and performance of the entire supply chain [6, 7]. The impact of supply chain disruptions is widespread, which may lead to negative consequences such as production delays, increased costs, decreased product quality, and loss of market share. Chowdhury et al. pointed out that supply chain disruptions caused by epidemics not only affect production and delivery but also impact the flow of information and finance in the supply chain [8]. Enterprises highly dependent on global supply chains are particularly vulnerable, with manufacturing and high-tech industries being particularly affected by the concentration of suppliers in specific regions [9]. In addition, market uncertainty caused by disruptions complicates operational planning for firms [10].

To cope with the impact of unexpected events on the supply chain, the concept of supply chain resilience has gradually gained attention. Enterprises can enhance supply chain resilience by strengthening supply chain flexibility, improving inventory management capabilities, and increasing the use of local suppliers. Enterprises in Europe and the United States have turned to “near-shoring” during the epidemic to reduce their reliance on transcontinental supply chains.

3. Case Analysis

3.1. Case Description

The manufacturing industry is an important pillar of the global economy, covering a wide range of processes from raw material processing to finished product manufacturing, including raw material procurement, production and processing, warehousing, and logistics and distribution. With the advancement of technology, the manufacturing industry is developing in the direction of intelligence, automation, and digital transformation. Modern manufacturing companies rely on efficient supply chain management to achieve cost control, improve production efficiency, and respond to market demand. Especially in the highly competitive global market environment, the manufacturing industry faces multiple pressures to reduce costs, improve product quality, and shorten lead times. During the pandemic, the global supply chain suffered severe disruptions, with many manufacturing companies facing shortages of raw materials, logistical delays, and production stoppages. According to the World Bank, the epidemic led to a nearly 20% drop in global trade in goods in 2020, with the manufacturing sector particularly affected, such as the global automotive industry, which was forced to shut down several factories due to a lack of semiconductor chips.

Apple’s supply chain is known for its high level of integration and global presence, covering the entire process from product design production to sales. Apple’s product design is primarily done in the United States, with design and engineering teams based at its headquarters. Apple’s production relies on a global supply chain, especially focused on foundries and suppliers in Asia. Apple has thousands of component suppliers around the world, located in Japan, South Korea, China, and the United States, producing key components such as chips, displays, and cameras. OEM giants such as Foxconn and PEGATRON undertake the major assembly of Apple products. Apple’s sales network covers both online and offline channels. Through online sales on Apple’s official website and App Store, as well as Apple Store retail stores and authorized retailers around the world, Apple directly faces consumers. Apple also promotes the distribution of products such as the iPhone in the global market through cooperation with telecom operators.

3.2. Outbreaks and Supply Chain Disruptions

3.2.1. Production Disruption

At the beginning of the epidemic, the factory blockade in China and Southeast Asia caused severe disruptions in Apple’s supply chain, with a lack of supply of key components such as chips, displays, and camera modules. According to the analysis, in the first quarter of 2020, Apple’s iPhone production dropped by about 20% year-on-year. In addition, the epidemic also led to production restrictions on key components such as chips and displays, causing Apple to face serious supply bottlenecks in the second quarter of 2020. the rebound of the Southeast Asian epidemic in 2021 exacerbated the difficulties in chip packaging and testing, leading Apple to repeatedly revise its production targets downward. Production of the iPhone 13 series was revised downward from 95 million units to approximately 83 million units, while the iPad and MacBook also faced severe supply shortages.

Logistics bottlenecks further impacted deliveries. Due to reduced flights and port congestion, the shipping and delivery cycles of Apple products were significantly lengthened, and the delivery of several new products (e.g., iPhone 13 and Apple Watch) was delayed by weeks to months, directly impacting the consumer experience. In addition, labor shortages at key supplier factories, such as Foxconn, during the peak of the epidemic also led to a decline in productivity, further crippling Apple’s production capacity.

To address supply chain challenges, Apple accelerated supplier diversification, shifted some production to India and Vietnam, and invested in digital management of the supply chain to improve resilience. At the same time, Apple increased inventory reserves of key components to cope with future supply chain fluctuations. These measures have eased production pressure to a certain extent, but Apple’s overall production and new product release pace are still deeply affected by the epidemic.

3.2.2. Disruption to Market Operations

Global shipping and logistics were severely affected by the outbreak. Transportation times were significantly extended as many flights were canceled. Statistics show that in April 2020, global freight traffic dropped by almost 20%. This situation led to an extension of Apple’s product delivery time by about 3-4 weeks, affecting the company’s market performance and customer satisfaction.

COVID-19 posed significant challenges to Apple’s operations in the market, including stagnation of offline retail business, delays in new product releases, and fluctuations in market demand. At the beginning of the epidemic, Apple closed a large number of Apple Stores around the world, especially in important markets such as China, Europe, and the U.S. The blockage of offline sales channels greatly affected the sales of its high-end products, forcing Apple to accelerate its shift to online sales.

In the face of increased online demand brought about by the epidemic, Apple quickly enhanced the shopping experience on its official website and strengthened online customer service and technical support, optimizing online sales channels along the way. In the second quarter of 2020, online sales grew by more than 20%, making up for some of the offline losses. In addition, due to supply chain disruptions, Apple had to delay the release of the iPhone 12 series and some new products, missing the traditional peak season and leading to a tight supply of high-end products.

Meanwhile, demand for home office and online learning surged, boosting sales of office equipment such as iPads and Macs. Apple also aggressively expanded its service business during the epidemic, with revenues from digital services such as Apple Music and Apple TV+ growing significantly, effectively sharing the pressure on hardware sales. In addition, to meet market demand, Apple launched preferential policies and payment programs and increased investment in the Chinese market, with revenue growth of more than 50% in China in the second quarter of 2020.

3.3. Supply Chain Disruption and Supply Chain Resilience

3.3.1. Diversified Supply Chain

Apple has increased its investment in production in India and plans to increase its production in India to 30% by 2025. This strategy aims to reduce its reliance on Chinese manufacturing and minimize the risk of future epidemics or trade frictions. By diversifying its supply chain, Apple can achieve more stable production in different regions. In addition, Apple has decentralized the sources of supply for key components, with semiconductor supply being multi-located by TSMC to ensure that chip production is not affected by disruptions in a single region. Apple has also promoted near-shore outsourcing and localization strategies. By establishing a production line for the Mac Pro in Texas, U.S.A., Apple has improved the efficiency of regional supply while shaping the local brand image.

3.3.2. Supplier Network Collaboration

Apple prioritizes access to important resources by establishing deep cooperative relationships with key suppliers. Apple’s close cooperation with Taiwan Semiconductor Manufacturing Company (TSMC) has helped it prioritize access to A-series and M-series chips during global chip shortages, guaranteeing smooth production of iPhones and Macs. Apple also actively invests in suppliers’ capacity and technology upgrades. The company provided technical support to OLED supplier LG Display to accelerate the production capacity of iPhone screens and co-invested in chip production with TSMC in the U.S. to diversify supply chain risks and reduce dependence on a single region. In addition, Apple maintains close communication with key suppliers to ensure timely information sharing and adjust production plans to meet changing market demands. By building a strong supplier network, Apple can react quickly in the face of unexpected events.

3.3.3. Technological Innovation

Apple uses big data and artificial intelligence technologies to optimize demand forecasting and inventory management to ensure that products can meet market demand promptly. Apple predicts sales trends through real-time data analysis, quickly adjusts production plans, and improves the responsiveness of the supply chain.

Through the above strategies, Apple successfully mitigated the impact of supply chain disruptions during the outbreak. In FY2020, Apple’s total revenue reached $274.5 billion, up 6% year-on-year. Of this, net income for the second quarter was $11 billion, showing strong performance despite supply chain challenges. Despite the supply chain issues, Apple successfully launched the iPhone 12 series in the second half of 2020 and recorded strong sales, driving rapid growth in fiscal 2021.

4. Supply Chain Resilience for Sustainable Supply Chain

Apple’s innovations in circular supply chains and recycling demonstrate how supply chain sustainability can be achieved through circular economy concepts. First, Apple makes extensive use of renewable and recyclable materials in its product designs. The touch engine in the iPhone 13 Pro utilizes 100 percent recycled rare earth elements, reducing reliance on new resources. This choice not only reduces the environmental impact of material extraction but also supports the long-term conservation of natural resources.

In terms of recycling, Apple has invested in the development of the “Daisy” dismantling robot, which specializes in dismantling old devices to recover metals, rare earth, and other scarce materials and reuse them in the manufacture of new products. As of 2020, Apple has collected over 1,000 tons of aluminum, copper, and cobalt through this recycling process. Through this intelligent recycling system, Apple has effectively reduced the generation of e-waste and realized the efficient use of resources.

In addition, Apple is committed to achieving its goal of 100% carbon neutrality for its global supply chain and products by 2030. As of 2021, 175 suppliers have already committed to using 100% renewable energy, avoiding about 18 million tons of carbon emissions per year. Such supply chain carbon neutrality initiatives not only improve the environment but also set an example for the entire industry while demonstrating corporate social responsibility.

In terms of collaboration, Apple works closely with its suppliers and has partnered with 175 suppliers around the world to promote the use of 100 percent renewable energy, thereby reducing carbon emissions by approximately 18 million tons per year and helping suppliers improve their sustainability. Apple’s Supply Chain Clean Energy Program encourages suppliers to switch to green energy, creating a win-win ecosystem. This management approach provides robust support for a sustainable supply chain of the future, which not only strengthens resilience to risk but also promotes the green transformation of the entire industry chain.

Apple’s circular supply chain and recycling strategy shows that in the future, through effective resource reuse and green innovation, enterprises can realize sustainable supply chain development while safeguarding production, thus bringing long-term benefits to the ecological environment and society.

5. Conclusion

This study analyzes the impact of COVID-19 on global manufacturing supply chains and discusses the responses of manufacturing firms to enhance supply chain resilience and achieve sustainable development. The epidemic has exposed the vulnerability of global supply chains, especially under the “just-in-time” model, where companies lack sufficient buffer space when facing unexpected situations. The study takes Apple as an example to describe its supply chain disruption performance and response strategy. During the epidemic, Apple faced supply shortages due to production disruptions and logistical bottlenecks and took measures such as diversifying its supply chain, improving supplier cooperation, and technological innovation to mitigate the impact. To achieve supply chain sustainability, Apple has made extensive use of recycled materials in product design, developed recycling technologies, and committed to achieving a carbon-neutral supply chain by 2030.

This study focuses on the special case of Apple, which cannot reflect the situation of the whole manufacturing industry. In addition, imperfect data is also a major problem. Since the data sources are mostly public information, it lacks a detailed analysis of each link in the supply chain, making it difficult to comprehensively reflect the differences in different regions and periods. The study is mainly based on data from the early stage of the epidemic and lacks an in-depth exploration of the long-term impact, especially in the context of global supply chain reorganization, where the future market remains highly uncertain. Future research should expand the sample scope, combine different industries, and collect more detailed data to provide more accurate supply chain resilience management recommendations.

First, the research object can be expanded to include enterprises of different sizes and industries in the analysis, especially small and medium-sized enterprises and non-high-tech industries, to enhance the generalizability of the research. Second, the long-term impact of supply chain resilience should be explored in depth, taking external factors such as geopolitics and climate change into account to better understand the performance of supply chains amidst future uncertainty. In addition, the breadth and depth of data should be increased to collect more granular supply chain operational data, such as supplier management details, inventory dynamics, and logistics cost changes, to quantitatively assess the effectiveness of different response measures. Finally, research on the application of digital technologies in the supply chain can be strengthened to explore how big data and artificial intelligence can more effectively forecast demand, manage inventory, and enhance supply chain resilience, thereby providing more practical guidance for building resilience and sustainable development of enterprises.