The master said calmly: "In the process of machining, we have used a lot of cutting fluids, these cutting fluids themselves have their own colors, but these cutting fluids in the process of use, will slowly become other colors, we have not found a law so far, I want to hear your views from experts." “

Yu Fan: "Excuse me, what color has it become?" Here's an example. ”

Master: "For example, we used to use a fully synthetic cutting fluid, and after using it for a while, the cutting fluid turned red. ”

Yu Fan replied with a smile: "Well, master, I would venture to guess whether the material you processed during that period was cemented carbide?" The cutter is also an alloy cutter? ”

Master: "Yes, you are right. ”

Yu Fan continued: "This is a typical cobalt precipitation phenomenon, and the formula of the fully synthetic cutting fluid often contains triethanolamine and sodium phosphate, which will react with the cobalt in the cemented carbide and the tool to form a complex, and then the cobalt ions are precipitated into the water, which sees the scene of the cutting fluid turning red." At this time, when you choose cutting fluid, you should choose to prevent cobalt precipitation, which can be solved. ”

At this time, another master also stood up: "However, what I see is a different color, after my machine tool cutting fluid has been used for a period of time, the color has become blue, and it was also transparent before." ”

Yu Fan turned his head and explained with a smile to the master: "This situation generally occurs when processing copper parts, and the cutting fluid reacts with copper, resulting in copper ions entering the water, and this phenomenon will occur. In addition, if the copper chips you process fall in the water tank and are not cleaned in time, this phenomenon will also occur, because copper, cutting fluid, and water tank will form a galvanic cell reaction and accelerate the precipitation of copper. ”

The workers nodded their heads.

At this time, the female worker, who thought she was in her forties, got up and asked, "What is the matter with turning black?" ”

Yu Fan: "It's getting black, in addition to seeing it turn black, do you often smell some unpleasant smells?" ”

The female master nodded again and again: "Yes, yes, there is often the smell of rotten eggs, and the smell is especially serious every time I come back from vacation." ”

Yu Fan: "It's because the cutting fluid has deteriorated." If the maintenance of the cutting fluid is not paid attention to, the concentration is too low, and the pH value is too low, the anaerobic bacteria will multiply in large numbers and grow geometrically, resulting in rancidity of the cutting fluid and the release of hydrogen sulfide gas at the same time. In this case, you should pay more attention, quickly add some fungicides, to see if you can control the bacteria, if you really can't control it, you can only replace the cutting fluid, and pay attention to maintenance when using it in the future. ”

The workers nodded their heads.

Yu Fan added: "In fact, you also see that the same thing, in different circumstances, will become different colors, each color has their own reason, when we observe the change of a phenomenon, that is, we should be the same as you, keep curious, ask more questions, people will progress, science and technology will progress." ”

The masters seemed very happy, as if they had found a chemical expert and took out all the problems that had accumulated over the years. You know, in the machinery factory, there are really few people who really understand chemistry, and everyone asks a lot of questions, one question is more professional than the other, one question is more tricky than the other, and there are even questions about mechanical design and so on. However, Yu Fan calmly answered all questions, from mechanism to characterization, from problem to solution ideas.

Time passed quickly, and it was almost time to get off work, but everyone was still unsatisfied. Director Shi only forcibly interrupted the sharing meeting: "Okay, okay, let's stop here today, Expert Yu and they are going back." ”

Everyone was reluctant to leave.

Director Shi held Yu Fan's hand again: "I know your professional ability is very strong, but I didn't expect it to be so powerful, in addition to chemistry, you know physics and biology very well, and you even understand our mechanical design and manufacturing." ”

Yu Fan waved his hand and said modestly: "I just know some fur, and I am ugly where I said it wrong." ”

Director Shi hurriedly thanked him: "You are too polite, it's not early, let's have a meal together in the evening and then hurry." ”

Yu Fan declined: "Thank you Director Shi for your kindness, we have other things to do when we go back, let's get together again next time." ”

Director Shi didn't forcibly stay, he accompanied Yu Fan and Cao Ben all the way to the car, and sent Yu Fan and them to the car, until Yu Fan's car drove away, Director Shi was still watching them in place and waving until they disappeared from view.

On the way back, Cao Ben sighed: "Hey, really, the sky has eyes, it seems that this customer will not fall, good people really have good rewards, right?" Old than. ”

Yu Fan grinned: "Good and evil will be rewarded in the end, and the way of heaven is good for reincarnation." Look up at the sky, who the sky bypasses. ”

Cao Ben also said: "Good and evil are rewarded, but the time has not yet come." ”

Yu Fan was also happy: "Indeed, good and evil will be rewarded in the end, no one can predict when it will come, while waiting, what we can do is to patiently enrich ourselves every day and find the truth about the operation of the world." ”

Cao Ben asked: "Old Yu, what do you mean?" “

Yu Fan: "Human life is very short, and we are more like a passerby when we come to this world. Have you ever wondered what is the significance of our coming into this world? Maybe before everyone comes to this world, we are in another parallel universe, each of us has received the same test paper, the content of the test paper is to let everyone come to the earth for a decades-long experience, and when we leave this world, we will return to that parallel universe, write what we have seen and thought in this life on the test paper, and finally hand in a satisfactory answer. It's just that after many people come to this world, they forget the test papers they came here and are attracted by this world of flowers. ”

Cao Ben asked again: "Then what should we do?" ”

Yu Fan: "Calm down and do your best." Fight bravely and make persistent efforts. It's like when we do an experiment, it's an experiment, but every time we do it, we do our best. But we don't have to suffer from gains and losses, because if the experiment fails, we can start again, and the same is true of life, as long as the awareness is in the present, it is a new beginning. ”

Cao Ben smiled bitterly: "I don't understand this a little, haha." But the topic you talked about today about color, I think it's very interesting, and I'll sort it out and teach it to the company's employees when I go back, so that they can talk about it to users when they encounter this kind of problem. ”

Yu Fan nodded and looked at the dark night sky, the street lights under the night sky flickered.

Yu Fan was thinking about something in his heart. Color?